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/ModelName.kt

@@ -5,26 +5,23 @@ package com.example.aiapp
  *
  * One constant rather than a literal in each place, because the two have to agree: a picker whose
  * options cannot say every state its button can display is one you can leave and not get back to.
- * It is also the Claude CLI's own word for "whatever is configured", so choosing it is a request
- * the session can act on rather than a name this app made up.
+ * It is also the Claude CLI's own word for "whatever is configured".
  */
 const val DEFAULT_MODEL = "default"
 
 /**
  * A model's name as a person reads it.
  *
- * Providers answer with their own full identifier -- Claude Code resolves `haiku` to
- * `claude-haiku-4-5-20251001` and reports that, which is the honest answer to "what is this session
- * using" and far too long for a button in a row that also has to hold Stop and Send.
+ * Providers answer with their own full identifier -- Claude Code resolves `haiku` to `claude-
+ * haiku-4-5-20251001` and reports that, which is the honest answer to "what is this session using"
+ * and far too long for a button in a row that also holds Stop and Send.
  *
  * So the two ends that identify nothing are dropped and nothing else is: the vendor prefix, which
  * is the same on every model this app can show, and the release date, which distinguishes builds of
- * one model rather than one model from another. What is left is the part somebody chose --
- * `haiku-4-5` -- and anything that does not look like that is returned untouched, since a name this
- * does not recognise is a name it has no business editing.
+ * one model rather than one model from another. Anything that does not look like that is returned
+ * untouched.
  *
- * A display decision, not a correction: the full name is what the session reports and what a reader
- * is shown when there is room for it.
+ * A display decision, not a correction: the full name is what the session reports.
  */
 fun modelLabel(model: String?): String {
     val name = model?.takeIf { it.isNotBlank() } ?: return DEFAULT_MODEL