Epic: background recording enablement — turnkey FGS switch, F-Droid now, Play declaration package, dark seams wired

[fdittgen-png]

Triage

Classification: epic. (4 of 6 signals)

1. Source files > 5 — 4 workflow files, recording_location_settings.dart seams, companion_auto_record_coordinator.dart trigger, gps_only_trip_wal.dart, docs/declaration package.
2. Distinct subsystems — CI workflows, Android manifests/Gradle, consumption providers, Play Console policy.
3. Architectural decision — repo-variable-gated FGS enable (one switch, zero code change on approval).
4. Cross-feature coordination — CI + Android + Play Console + on-device validation.

Validation needed

@fdittgen-png — please confirm before I file the child issues:

• You agree this is an Epic (not a single task).
• The proposed task breakdown below is correct and complete.
• File each child issue in the listed order.

Problem statement

Background recording is architecturally complete but dark in every shipped Android build: Play builds dropped the FGS_FORM_APPROVED define (#3376) because Play's upload API 403s until the Foreground services declaration is completed in Play Console — and that declaration was never findable because (1) it lives under Monitor and improve → App content → Foreground services (not under any "background" heading — Android's background execution IS a foreground service with a persistent notification), and (2) the task typically only appears after an artifact declaring the FGS permissions reaches a track, which our API-only pipeline could never achieve (the 403 catch-22). Without the FGS: background GPS batches to ~5 s, AutoRecordForegroundService reports unavailable, CDM/battery-exemption/motion-gating are all no-ops. F-Droid needs no form and could ship the FGS today; iOS already records in background (plist location + bluetooth-central modes, ungated).

Target design

• Turnkey switch: all Play-bound workflows read the define from a repo variable (vars.FGS_FORM_APPROVED) — after the declaration clears, flipping ONE GitHub variable enables everything (Dart flag + manifest overlay swap in lockstep, per the feat(android): un-throttle trip GPS + re-enable Auto service when the Play FGS form clears (restore points documented in-code) #3173 mechanised restore).
• F-Droid + sideload dev-APK builds get the FGS now (no Play review path).
• A complete declaration package: manual internal-track upload recipe to surface the form, per-type declaration texts (location, connectedDevice), demo-video scripts. Only the Play Console submission itself remains a human step.
• The two dark seams wired: CDM ensureAssociated production trigger (feat(android): Companion Device Manager association to auto-start the OBD2 connectedDevice FGS from background — Epic #3314 #3320 leftover) and GpsOnlyTripWal.flushNow on backgrounding.

Proposed tasks

• Task 1: Repo-variable-gated FGS define → ci: gate the FGS_FORM_APPROVED define on a repo variable across all Play-bound workflows (epic #3417 task 1) #3434 — daily-beta.yml, daily-github-release.yml, dev-apk.yml read vars.FGS_FORM_APPROVED; pin test for the off-default.
• Task 2: Enable FGS on F-Droid + dev-APK now → ci(fdroid): ship the location FGS on F-Droid + dev-APK sideload builds now — no Play form applies (epic #3417 task 2) #3435 — fdroid-publish.yml define (overlay exists); dev-APK sideload build for on-device validation.
• Task 3: Declaration package → docs(play): FGS declaration package — surfacing recipe, declaration texts, demo-video scripts (epic #3417 task 3) #3436 — exact Play Console walkthrough, manual internal-track upload recipe, declaration texts + video scripts for both FGS types. (User action: submit.)
• Task 4: Wire CDM ensureAssociated trigger → feat(obd2): wire the CDM ensureAssociated production trigger at first manual pinned-dongle trip start (epic #3417 task 4) #3437 — first manual OBD2 trip start with a pinned dongle, feature-boundary-safe.
• Task 5: GpsOnlyTripWal.flushNow on app backgrounding → fix(consumption): flush the GPS-only trip WAL on app backgrounding (epic #3417 task 5) #3438 — currently test-only.
• Task 6: On-device validation matrix → chore(consumption): on-device background-recording validation matrix on the FGS sideload build (epic #3417 task 6) #3439 — bg GPS cadence 1 s, OBD2 stream survival, auto-record background arming, battery-exemption prompt, motion gating.

Out of scope

• refactor(consumption): host the recording loop in a dedicated background isolate — Epic #3314 #3321 recording-isolate cutover — only if validation shows process kills.
• ACCESS_BACKGROUND_LOCATION (Manual store-console tasks for Sparkilo open testing + TestFlight #1498) — deliberately NOT needed (foreground-started location FGS works on while-in-use permission).
• iOS — already functional.