Thin the app's comments

The same pass the server had, on the Kotlin side: comments restating what
the code says are gone, and the ones recording a measurement, a constraint
or an incident are kept but cut to a few lines each. 6540 comment lines to
5674, and 920 lines off the app.

Two doc comments had drifted onto the item above the one they describe --
`contextAfter`'s onto `sessionWorking` in Events.kt, and `UsageMonitor`'s
equivalent on the server was fixed in the previous commit. Each is back on
its own item, which is the only non-comment line this diff moves.

The comments are reflowed to the column limit at their own indentation:
several were written wide, and ktfmt re-wrapped them into lines holding a
single orphan word. `/tmp` script, not kept -- ktfmt is idempotent over the
result, which is the check.

Left alone deliberately: this codebase's remaining comment density is high
because the comments carry things the code cannot say -- what a null means,
what a number was measured against, which bug a guard exists for. Of the
238 one-line doc comments in the app, five were pure restatement of the
name and were removed; the rest each say something the signature does not.

ktfmtFormat, compileDebugKotlin, lintDebug and testDebugUnitTest pass;
cargo test (127), clippy --all-targets and fmt still clean.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

app/androidApp/src/main/kotlin/com/example/aiapp/UsageDialog.kt

@@ -27,17 +27,14 @@ import java.time.OffsetDateTime
  * A dialog rather than a screen. Usage is something you check *against* what you were reading --
  * "can I start this" is asked with the transcript still on screen -- and pushing a whole screen for
  * it took the session away to answer a question about the session. It also has no navigation of its
- * own: there is nothing here to open, so the only thing its Back could ever have meant was "put
- * this away", which is what dismissing does. The system back gesture dismisses it, since a `Dialog`
- * handles that itself.
+ * own, so the only thing its Back could ever have meant was "put this away".
  */
 @Composable
 fun UsageDialog(feed: UsageFeed, onDismiss: () -> Unit) {
-    // A plain Dialog rather than an AlertDialog, for the spacing alone. AlertDialog fixes the
-    // gaps between its title, its content and its buttons at sizes meant for a sentence of prose
-    // and a decision; this is a dense read-out, and those gaps left a band of empty dialog above
-    // Close that was taller than a bar. Everything else here is what AlertDialog would have
-    // drawn -- the same container colour, the same corner -- so nothing about it looks foreign.
+    // A plain Dialog rather than an AlertDialog, for the spacing alone. AlertDialog fixes the gaps
+    // between its title, content and buttons at sizes meant for a sentence of prose and a decision;
+    // this is a dense read-out, and those gaps left a band of empty dialog above Close that was
+    // taller than a bar.
     Dialog(onDismissRequest = onDismiss) {
         Surface(
             shape = MaterialTheme.shapes.extraLarge,
@@ -49,11 +46,9 @@ fun UsageDialog(feed: UsageFeed, onDismiss: () -> Unit) {
                     modifier = Modifier.fillMaxWidth(),
                 ) {
                     // Deliberately not subtitled with the provider this was opened from. These
-                    // numbers belong to an account on a particular machine, reported by whichever
-                    // paid service answered there -- naming the session's provider here made an
-                    // echo session's screen read "echo" above a line reading "claude", which is a
-                    // claim about echo that nothing measured. Each machine names itself and the
-                    // service it came from, which is the true scope.
+                    // numbers belong to an account on a particular machine -- naming the session's
+                    // provider here made an echo session's screen read "echo" above a line reading
+                    // "claude". Each machine names itself and the service it came from.
                     Text(
                         "Usage",
                         style = MaterialTheme.typography.headlineSmall,
@@ -69,10 +64,9 @@ fun UsageDialog(feed: UsageFeed, onDismiss: () -> Unit) {
                     }
                 }
                 Spacer(Modifier.height(8.dp))
-                // Scrolls rather than being trimmed: a machine can report any number of windows
-                // and there can be any number of machines, and a dialog is the one place where
-                // running out of room is silent. `fill = false` so a short read-out keeps a short
-                // dialog instead of stretching to the window.
+                // Scrolls rather than being trimmed: a machine can report any number of windows and
+                // there can be any number of machines, and a dialog is the one place where running
+                // out of room is silent. `fill = false` so a short read-out keeps a short dialog.
                 Column(Modifier.weight(1f, fill = false).verticalScroll(rememberScrollState())) {
                     UsageBody(feed.snapshots)
                 }
@@ -93,8 +87,8 @@ private fun UsageBody(state: LoadState<List<UsageSnapshot>>) {
             is LoadState.Error -> Text(current.message, color = MaterialTheme.colorScheme.error)
             is LoadState.Loaded ->
                 if (current.value.isEmpty()) {
-                    // Not an error and not a blank screen: no machine offers a paid service,
-                    // so there is genuinely nothing to report and saying so is the answer.
+                    // Not an error and not a blank screen: no machine offers a paid service, so
+                    // there is genuinely nothing to report and saying so is the answer.
                     Text(
                         "No machine here runs anything with usage limits.",
                         style = MaterialTheme.typography.bodyMedium,
@@ -103,17 +97,16 @@ private fun UsageBody(state: LoadState<List<UsageSnapshot>>) {
                 } else {
                     // No card around each machine. A card is a step up the surface ladder, and
                     // inside a dialog -- itself a raised surface -- the step barely renders while
-                    // costing 16dp of padding on every side. What separates one machine from the
-                    // next is the line naming it, which is enough for a list this short.
+                    // costing 16dp on every side. What separates one machine from the next is the
+                    // line naming it.
                     current.value.forEachIndexed { index, snapshot ->
                         if (index > 0) {
                             Spacer(Modifier.height(20.dp))
                         }
-                        // Machine and service on one line: which account these numbers belong to
-                        // is decided by both together, and stacked as a heading over a subtitle
-                        // they read as a section of their own rather than as the label they are.
-                        // Small and quiet, because the numbers below are what somebody opened
-                        // this to see.
+                        // Machine and service on one line: which account these numbers belong to is
+                        // decided by both together, and stacked as a heading over a subtitle they
+                        // read as a section of their own. Small and quiet, because the numbers
+                        // below are what somebody opened this to see.
                         Text(
                             "${snapshot.setupName.ifEmpty { snapshot.setup }} · ${snapshot.provider}",
                             style = MaterialTheme.typography.bodySmall,
@@ -121,8 +114,8 @@ private fun UsageBody(state: LoadState<List<UsageSnapshot>>) {
                         )
                         SnapshotState(snapshot)
                         snapshot.windows.forEachIndexed { windowIndex, window ->
-                            // Between the bars, not after the last one: a trailing gap here is
-                            // what put a band of empty dialog above the Close button.
+                            // Between the bars, not after the last one: a trailing gap here is what
+                            // put a band of empty dialog above the Close button.
                             if (windowIndex > 0) {
                                 Spacer(Modifier.height(12.dp))
                             }
@@ -139,8 +132,7 @@ private fun UsageBody(state: LoadState<List<UsageSnapshot>>) {
  *
  * The distinction the old single message could not draw. A machine nobody has logged in on is
  * working exactly as somebody set it up, so it reads as a plain statement -- marking it would be
- * the interface nagging about a decision already made, and would dilute the marks that do mean
- * something. Only the two faults are coloured as faults.
+ * the interface nagging about a decision already made. Only the two faults are coloured as faults.
  */
 @Composable
 private fun SnapshotState(snapshot: UsageSnapshot) {
@@ -152,8 +144,8 @@ private fun SnapshotState(snapshot: UsageSnapshot) {
                 style = MaterialTheme.typography.bodyMedium,
                 color = MaterialTheme.colorScheme.onSurfaceVariant,
             )
-        // Reached but refused, versus never reached at all: different things to go and do,
-        // so they say different things rather than sharing one "unavailable".
+        // Reached but refused, versus never reached at all: different things to go and do, so they
+        // say different things rather than sharing one "unavailable".
         "failed" ->
             Text(
                 snapshot.detail ?: "Couldn't read the limits from this machine.",
@@ -200,10 +192,9 @@ private fun WindowBar(window: UsageWindow) {
 /**
  * "resets in 3h 12m" -- close enough for deciding whether to start a big task -- or nothing.
  *
- * Null for a window that is not running, which is the case this row has always drawn as nothing and
- * is right to: there is no end to report. What it used to get wrong is the other missing case, a
- * timestamp that arrived and could not be read: that was printed raw, so a parse failure appeared
- * as an ISO string in the middle of a sentence written for a person. Both cases are named in
+ * Null for a window that is not running: there is no end to report. What this used to get wrong is
+ * the other missing case, a timestamp that arrived and could not be read -- printed raw, so a parse
+ * failure appeared as an ISO string in a sentence written for a person. Both are named in
  * [WindowEnd], and the session bar words them the same way.
  */
 private fun resetLine(window: UsageWindow): String? =