Add v3.05.0 safety review documentation and Hamilton test suite docs

- firmware/custom-v305.mdx: watchdog, timeout protection, error codes,
  I2C return checks, do_tune() safety, DiSEqC fixes, hardware validation
- tools/safety-testing.mdx: 55-test adversarial suite covering DiSEqC
  abuse, tune parameter abuse, I2C address abuse, state machine violations,
  boundary conditions, rapid-fire stress, and invalid vendor commands
- Updated version comparison with v3.05 tab and architectural table
- Sidebar entries for both new pages

site/astro.config.mjs

@@ -97,6 +97,7 @@ export default defineConfig({
             { label: 'FW2.13 Variants', slug: 'firmware/fw213-variants' },
             { label: 'Custom v3.01', slug: 'firmware/custom-v301' },
             { label: 'Custom v3.02', slug: 'firmware/custom-v302' },
+            { label: 'Custom v3.05', slug: 'firmware/custom-v305' },
             { label: 'Storage Formats', slug: 'firmware/storage-formats' },
           ],
         },
@@ -120,6 +121,7 @@ export default defineConfig({
             { label: 'Debugging', slug: 'tools/debugging' },
             { label: 'TS Analyzer', slug: 'tools/ts-analyzer' },
             { label: 'Spectrum Analysis', slug: 'tools/spectrum-analysis' },
+            { label: 'Safety Testing', slug: 'tools/safety-testing' },
           ],
         },
         {