ci: skip APK sanity-check on docs/tools/CI-only changes

The Lint & Compile check takes ~2h, yet it runs on EVERY push/PR to main or
development — including commits that touch no APK code (a README typo, a shell
tool under tools/, a CI tweak). Add paths-ignore so the build is skipped when a
change touches ONLY non-APK paths: **.md, docs/**, controller/docs/**, tools/**
(rootfs/proot builders), .github/** (CI config), LICENSE, .gitignore.

If ANY app source/gradle/resource file is also touched, the check still runs
(paths-ignore only skips when ALL changed files match). Tags / release builds
are unaffected (separate workflows). Future work: finer code-vs-noncode logic.

NOTE: if 'Lint & Compile Check' is a REQUIRED status in branch protection, a
docs-only PR will show the check as never-run and could be blocked; in that case
either unmark it required or add a companion always-green job for ignored paths.

Author: luisguzman-adfa

.github/workflows/android-sanity-check.yml

@@ -6,8 +6,24 @@ on:
   # got two redundant concurrent runs. Feature branches are covered by their PR.
   push:
     branches: [ "main", "development" ]
+    paths-ignore:
+      - '**.md'
+      - 'docs/**'
+      - 'controller/docs/**'
+      - 'tools/**'
+      - '.github/**'
+      - 'LICENSE'
+      - '.gitignore'
   pull_request:
     branches: [ "main", "development" ]
+    paths-ignore:
+      - '**.md'
+      - 'docs/**'
+      - 'controller/docs/**'
+      - 'tools/**'
+      - '.github/**'
+      - 'LICENSE'
+      - '.gitignore'
 
 # Supersede in-flight runs: when a newer commit lands on the same branch/PR, cancel
 # the older run so a fixup doesn't leave a zombie ~50-min lint job running.