docs(14.2.1): create phase plan

.planning/phases/14.2.1-translate-plugin/14.2.1-RESEARCH.md

@@ -699,21 +699,18 @@ DATA_r3t6y0ab_END
 
 A1–A3 are execution details, not stack choices. A4 follows locked D-08.
 
-## Open Questions
+## Open Questions (RESOLVED)
 
-1. **Proof fixture location**
+1. **Proof fixture location — RESOLVED**
    - What we know: D-17 wants a fixture model; host checkout is empty/missing.
-   - What's unclear: host app plugin vs test-only fixture.
-   - Recommendation: plugin integration test + host boot without Journal; no third production plugin.
+   - Resolution: use a test-only fixture plugin/model in the translate plugin integration harness, plus a real `sm-grzybyfunkcjonalne-app` host boot with user+translate and no third production plugin. Plans 02–04 implement this split.
 
-2. **Admin session for Translator**
+2. **Admin session for Translator — RESOLVED**
    - What we know: PHP uses Laravel `Session::put(SESSION_LOCALE)`.
-   - What's unclear: SummerCMS public requests may not have a session store yet (admin uses JWT cookie).
-   - Recommendation: signed cookie `golem15.translate.locale` plus `locale_manually_set`; document as the Go analog of session+cookie.
+   - Resolution: use a signed remembered-locale cookie named `golem15.translate.locale`, with `locale_manually_set` remaining a separate flag-only cookie; validate the remembered code against enabled locales on every request. Plan 01 implements this Go session analog.
 
-3. **Phase 15 ROADMAP depends_on**
-   - Deferred idea: `$gsd-phase --edit 15` not done in discuss.
-   - Recommendation: planner notes it; do not block this phase.
+3. **Phase 15 ROADMAP depends_on — RESOLVED**
+   - Resolution: keep the ROADMAP dependency edit deferred and out of Phase 14.2.1. The plans document Phase 15 as the consumer without mutating its roadmap metadata or blocking this phase.
 
 ## Environment Availability