docs(07): create phase 7 execution plans for DKV fleet module

6 plans covering full pipeline: PDF parsing foundation (Wave 0),
inbox providers + export/SMTP services (Wave 1), pipeline
orchestration + frontend pages + settings UI (Wave 2). Includes
D-06 MailModule DB-config migration and Nyquist validation strategy.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.planning/phases/07-dkv-fleet-module/07-RESEARCH.md

@@ -907,27 +907,15 @@ function resolveFahrzeug(
 
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-## Open Questions
+## Open Questions (RESOLVED)
 
-1. **pdf-parse v2 LoadParameters Buffer key**
-   - What we know: Documentation shows `{ url: '...' }` and `{ data: buffer }` loading modes
-   - What's unclear: Exact property name for Buffer loading (`data` vs `buffer` vs `content`)
-   - Recommendation: Wave 0 must include a 10-line test script: `new PDFParse({ data: fs.readFileSync('user-files/invoice.pdf') })` — if it fails, try `{ url: 'file://...' }` as fallback
+1. **pdf-parse v2 LoadParameters Buffer key** — RESOLVED: `{ data: buffer }` is the correct key per TypeDoc LoadParameters interface. Plan 01 Task 4 (Wave-0-Validation) runs an empirical test against `user-files/invoice.pdf` before the parser service is written — this resolves the assumption at runtime.
 
-2. **DKV PDF exact regex for transaction rows**
-   - What we know: VEHICLE: marker anchors vehicle blocks; each row has date, station, km, product, quantity, unit
-   - What's unclear: Exact column spacing, whether amounts (Netto/Brutto) are on the same row or summary rows
-   - Recommendation: Wave 0 must print the raw text from invoice.pdf and examine it before writing regex
+2. **DKV PDF exact regex for transaction rows** — RESOLVED: Plan 01 Task 4 (Wave-0-Validation) prints raw PDF text from `user-files/invoice.pdf` and validates the regex before building `dkv-parser.service.ts`. Regex in Pattern 4 is the starting point; adjustments recorded in 07-01-SUMMARY.md.
 
-3. **ScheduleModule in AppModule**
-   - What we know: `@nestjs/schedule@^6.1.3` is installed, NOT in AppModule imports
-   - What's unclear: Whether any other planned module (future phase) also needs it — no conflict either way
-   - Recommendation: Add `ScheduleModule.forRoot()` to AppModule in Wave 0, then DkvModule uses `SchedulerRegistry`
+3. **ScheduleModule in AppModule** — RESOLVED: Plan 01 Task 2 adds `ScheduleModule.forRoot()` to AppModule. No conflict with other modules — `ScheduleModule.forRoot()` is idempotent.
 
-4. **Settings sidebar restructuring**
-   - What we know: Settings currently has only "Dashboard" category (Widgets + Calendar)
-   - What's unclear: Whether to add "Allgemein > SMTP" as a new top-level sidebar category or embed it in an existing one
-   - Recommendation: Add a "Allgemein" category section to `SettingsSidebar` with SMTP as the first item — clean separation from dashboard settings
+4. **Settings sidebar restructuring** — RESOLVED: Add "Allgemein" top-level category to `SettingsSidebar` with SMTP as first item. Plan 05/06 (frontend) implements this.
 
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