2026-05-09: Fix dev DB consistency + web dark-mode navigation flash

Context

Two issues in scope:

Deleting asset in Docker dev then opening Tauri dev can show deleted asset again.
Intermittent dark-mode flash appears in web app during route navigation.

Additional doc request:

Remove Google Drive development guidance from active docs (historical plan docs excluded).

#	Convention	Applies	Plan handling
1	Documentation parity	Yes	Update active docs for DB behavior and remove Google Drive guidance
2	4 test gates required	Yes	Run backend build+unit+e2e and frontend unit+e2e
3	Self-review before implementation	Yes	File list and acceptance mapping included below
4	Endpoint coverage (Bruno + Swagger)	No	No new endpoint
5	Bug-to-Test rule	Yes	Add regression test(s) for dark-mode navigation behavior
6	Seed/test data isolation	Yes	Keep tests independent from seeded records
7	Transaction invariants	No	No asset transaction rule change planned
8	Plan history doc before implementation	Yes	This file
9	Infra test gate	Yes	Re-run affected Docker/Tauri scripts and verify behavior
10	Environment compatibility	Yes	Keep commands compatible with standalone docker-compose setup
11	Do-no-harm baseline	Yes	Reproduce baseline before/after for key behavior
12	Execution Summary required	Yes	Append section after implementation and test gates
13	Doc grep rule for renamed paths	Yes	Run grep on old path references and update active docs

Tauri runtime mode fix (src-tauri/src/lib.rs)
- Decouple dev/prod DB path selection from git-tag cleanliness.
- Ensure tauri:dev always uses backend/.data/strata-dev.db.
Docker dev hardening (package.json)
- Force DB_FILE=strata-dev.db in docker:dev, docker:reset, docker:nuke.
Tauri reset helpers alignment (scripts/tauri-reset.sh, scripts/tauri-nuke.sh)
- Delete backend/.data/strata-dev.db (shared dev DB), not legacy Strata-Dev path.
Dark-mode flash fix (front/src/layouts/MainLayout.astro, related frontend files as needed)
- Make dark theme application deterministic before paint across route navigation.
Regression tests
- Add/adjust frontend automated tests to cover dark mode persistence on navigation.
Active docs cleanup
- Remove Google Drive guidance from active docs pages.
- Update active docs still referencing stale dev data paths.

Acceptance criterion	Planned item(s)
Docker dev + Tauri dev share same dev DB in practice	1, 2, 3
Deleted asset does not reappear when switching Docker dev → Tauri dev	1, 2, 3
Dark mode does not flash light during navigation	4, 5
Active docs no longer mention Google Drive dev workflow	6
Required test gates all pass	5 + test gate run

Commit: not committed yet (working tree changes only)

Tauri runtime mode now uses build profile (debug_assertions) instead of git-tag cleanliness to choose dev/prod DB paths (src-tauri/src/lib.rs).
Docker dev scripts now force DB_FILE=strata-dev.db for docker:dev, docker:reset, and docker:nuke (package.json).
Tauri reset helpers now target shared dev DB at backend/.data/strata-dev.db (scripts/tauri-reset.sh, scripts/tauri-nuke.sh).
Dark-theme prepaint logic now sets class + color-scheme + fallback colors before paint to reduce navigation flash (front/src/layouts/MainLayout.astro, front/src/lib/theme.ts, front/src/stores/themeStore.ts).
Added regression coverage for dark mode navigation persistence (front/e2e/theme.spec.ts) and stabilized smoke heading assertions for existing async/hydration timing (front/e2e/smoke.spec.ts).
Removed Google Drive guidance from active docs and aligned active DB-path docs with shared dev DB behavior (configuration.md, desktopapp.md, quickstart.md, recovery.md).

Added front/src/test-setup.ts storage polyfill so frontend unit tests run reliably in current Node/Vitest environment.
Stabilized existing smoke e2e assertions (front/e2e/smoke.spec.ts) because full test gate surfaced pre-existing heading timing/strict-locator failures unrelated to core feature logic.

Git-describe-based env labeling is not safe as a runtime mode switch for tauri:dev; clean tagged checkouts can be misclassified.
In this environment, Playwright browser binaries were missing and required npx playwright install before e2e tests could run.