Clean up the app: one fix per rule already written down somewhere else

A pass over every Kotlin file, fixing each place a rule the codebase had
already learned was applied to only one member of its set:

- Notifications: checkSelfPermission(POST_NOTIFICATIONS) on Android 12 and
  below answers "denied" for a permission that does not exist there, so
  every notification on API 24-32 was silently dropped. Version-guarded;
  before 13 the app-level switch is the whole answer.
- The permission-mode list was written three times and had drifted: the
  import screen was missing "plan". One list in Api.kt now.
- The import screen's delete refetched the whole list through a loading
  spinner -- the exact fault the session list's delete already fixed and
  documented. It now removes only the deleted row.
- The import screen truncated paths at a hardcoded 40 characters; it now
  uses StartEllipsis against the row's real width, like the models screen.
- warm() bypassed the partsOf cache built for it, re-scanning every loaded
  message per page, and warmed a multi-block memory note under keys no row
  looks up. It now mirrors transcriptUnits through the same caches.
- The transcript's data model (TranscriptItem, foldEvent, joinPages, warm)
  moved out of SessionScreen.kt into TranscriptItems.kt: pure folding with
  no screen in it, changing for unrelated reasons in the same file.
- One image fetch/decode/failed block was written twice; it is
  rememberSessionBitmap in SessionImage.kt now.
- Lint is fully clean: android.media.ExifInterface replaced with the
  androidx one (the framework copy lacks the hostile-image parsing fixes,
  and these images arrive from outside the phone), highlights bumped to
  1.1.0, and the notification fix above closed InlinedApi.
- Dead weight out: an unused act() onFailure parameter, and five orphaned
  or misattached doc comments (UserBubble carried SessionImage's doc).

Verified: ktfmt, compileDebugKotlin, lintDebug (0 issues), server suite
(93 passed), clippy and rustfmt clean; exercised on the emulator against a
real imported transcript -- paging, tool groups, block rendering, no
crashes.

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

app/gradle/libs.versions.toml

@@ -28,8 +28,13 @@ zxing-embedded = "4.3.0"
 markdown-renderer = "0.45.0"
 # Syntax highlighting for a tool call's input. Same reasoning as the markdown
 # renderer: a language's lexical rules are somebody else's specification.
-# Latest stable, checked 2026-08-29 against Maven Central.
-highlights = "1.0.0"
+# Latest stable, checked 2026-08-31 against Maven Central.
+highlights = "1.1.0"
+# The support ExifInterface rather than android.media's, which lint warns off:
+# the framework one is missing formats and the fixes for parsing hostile
+# images, and images here arrive from outside the phone. Latest stable,
+# checked 2026-08-31 against Google Maven.
+androidx-exifinterface = "1.4.2"
 # Declared rather than inherited for the same reason as core-ktx: SessionScreen
 # now calls repeatOnLifecycle/LocalLifecycleOwner directly, to hold the event
 # stream open only while the screen is on screen. Latest stable, checked
@@ -59,6 +64,7 @@ desugar-jdk-libs = { module = "com.android.tools:desugar_jdk_libs", version.ref
 # theme, so the app's Catppuccin scheme is what it draws with.
 markdown-renderer = { module = "com.mikepenz:multiplatform-markdown-renderer-m3", version.ref = "markdown-renderer" }
 highlights = { module = "dev.snipme:highlights", version.ref = "highlights" }
+androidx-exifinterface = { module = "androidx.exifinterface:exifinterface", version.ref = "androidx-exifinterface" }
 # Declared directly rather than through the plugin's `compose.*` accessors,
 # which are deprecated as of CMP 1.11.
 compose-runtime = { module = "org.jetbrains.compose.runtime:runtime", version.ref = "compose-multiplatform" }