Remove internal filament management, integrate FilamentDB, add job detail page

Filament removal:
- Deleted app/models/filament.py, routers/filaments.py, templates/filaments.html
- Migration 0009: drops filaments table and filament_id FK from print_jobs
- Removed Filaments from sidebar and all internal references

FilamentDB integration (read-only):
- app/filamentdb.py: GET /reports/stock with 5-min in-memory cache
- available_materials() / available_colors() populate job form dropdowns
- Falls back to static constants if FilamentDB unreachable
- Dashboard filament count now from FilamentDB rolls_in_stock
- FILAMENTDB_URL added to .env.install; httpx added to requirements

Job detail page (/jobs/{id}):
- Two cards: Job info (customer, material, printer, bracket, timing, cost)
  and File & Geometry (bounding box + volume from stl_cache)
- Log timeline with Add Entry modal
- Filename in jobs list links to detail page

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

app/main.py

@@ -5,7 +5,7 @@ from fastapi import FastAPI, Request
 from fastapi.responses import JSONResponse
 
 from app.db import check_db, run_migrations
-from app.routers import filaments, pricing, print_jobs, printer_types, printers, todos
+from app.routers import pricing, print_jobs, printer_types, printers, todos
 from app.routers import ui
 
 logging.basicConfig(
@@ -41,7 +41,6 @@ async def unhandled_exception(request: Request, exc: Exception):
 # JSON API
 app.include_router(printer_types.router, prefix="/api")
 app.include_router(printers.router, prefix="/api")
-app.include_router(filaments.router, prefix="/api")
 app.include_router(print_jobs.router, prefix="/api")
 app.include_router(todos.router, prefix="/api")
 app.include_router(pricing.router, prefix="/api")