ci: drop pull_request triggers + add cancel-in-progress concurrency

Every commit on dev that's part of an open PR fires each workflow
TWICE: once for the push event and once for the pull_request event
(observable in run #43 + #44 for the same SHA in android.yml, same
shape across test-web.yml and test-go.yml). The two runs check the
exact same SHA — pure waste.

Drop the pull_request trigger from test-web.yml, test-go.yml, and
android.yml. The dev push already exercises every check that a PR
would re-run. This repo has no fork PRs to cover, which is the only
case pull_request would catch that push doesn't.

Add a concurrency group keyed on workflow + ref with
cancel-in-progress: true to every workflow including release.yml.
Rapid re-pushes (or force-moving the per-day tag) now cancel the
older in-flight run instead of stacking.

.gitea/workflows/android.yml

@@ -17,10 +17,12 @@ on:
     paths:
       - 'android/**'
       - '.gitea/workflows/android.yml'
-  pull_request:
-    branches: [main]
-    paths:
-      - 'android/**'
+
+# pull_request trigger intentionally omitted — see test-web.yml for
+# the rationale (single-author repo, push covers PR-merge equivalent).
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
 
 env:
   # Silences the JDK 22+ "restricted method in java.lang.System has been

.gitea/workflows/release.yml

@@ -26,6 +26,13 @@ on:
       - '**/*.md'
   workflow_dispatch:
 
+# Force-moving the per-day tag (or rapidly re-pushing to main) should
+# supersede the in-flight build — the operator explicitly wants the
+# later commit to win.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   release:
     runs-on: go-ci

.gitea/workflows/test-go.yml

@@ -31,17 +31,12 @@ on:
       - 'cmd/**'
       - '.golangci.yml'
       - '.gitea/workflows/test-go.yml'
-  pull_request:
-    branches: [main]
-    paths:
-      - '**/*.go'
-      - 'go.mod'
-      - 'go.sum'
-      - 'sqlc.yaml'
-      - 'internal/**'
-      - 'cmd/**'
-      - '.golangci.yml'
-      - '.gitea/workflows/test-go.yml'
+
+# pull_request trigger intentionally omitted — see test-web.yml for
+# the rationale (single-author repo, push covers PR-merge equivalent).
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
 
 jobs:
   test:

.gitea/workflows/test-web.yml

@@ -1,8 +1,10 @@
 name: test-web
 
-# Web SPA: vitest + svelte-check. Runs on push to dev/main and PRs to
-# main, scoped to web/** changes only — Go-only or Flutter-only diffs
-# don't trigger this workflow.
+# Web SPA: vitest + svelte-check. Runs on push to dev/main only —
+# the `pull_request` trigger is intentionally omitted because every
+# branch on this repo is local-only (no fork PRs), so the dev push
+# fully covers what a PR run would re-execute. Keeping both events
+# doubled CI cost on every commit.
 
 on:
   push:
@@ -10,11 +12,13 @@ on:
     paths:
       - 'web/**'
       - '.gitea/workflows/test-web.yml'
-  pull_request:
-    branches: [main]
-    paths:
-      - 'web/**'
-      - '.gitea/workflows/test-web.yml'
+
+# Cancel an earlier in-flight run for the same ref when a newer
+# commit arrives. With cancel-in-progress, rapid re-pushes don't
+# pile up zombie runs.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
 
 jobs:
   test: