chore: rename project from idfoto to relicario

Sweeping rename across crates, CLI binary, WASM bindings, extension, docs,
and vault metadata paths. Git remote updated to relicario.git.

- crates/idfoto-{core,cli,wasm} -> crates/relicario-{core,cli,wasm}
- IdfotoError -> RelicarioError
- IDFOTO_IMAGE env var -> RELICARIO_IMAGE
- ~/.config/idfoto -> ~/.config/relicario
- .idfoto/ vault metadata dir -> .relicario/ (breaking; pre-release)
- Binary name idfoto -> relicario
- Extension wasm module idfoto_wasm -> relicario_wasm
- Storage key idfotoSettings -> relicarioSettings
- All doc filenames and content references updated

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

extension/icons/relicario-logo.svg

@@ -0,0 +1,30 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 128 128" fill="none">
+  <!-- ID card outer body -->
+  <rect x="16" y="20" width="96" height="88" rx="6" fill="#0d1117" stroke="#58a6ff" stroke-width="3"/>
+
+  <!-- Photo rectangle (left side, dominant) -->
+  <rect x="26" y="32" width="44" height="64" rx="2" fill="#58a6ff"/>
+
+  <!-- Silhouette in photo (cartoony connected portrait) -->
+  <path d="M 28 96
+           L 28 92
+           C 28 84, 34 79, 42 77
+           L 42 73
+           C 38 71, 36 66, 36 60
+           C 36 52, 41 46, 48 46
+           C 55 46, 60 52, 60 60
+           C 60 66, 58 71, 54 73
+           L 54 77
+           C 62 79, 68 84, 68 92
+           L 68 96 Z" fill="#0d1117"/>
+
+  <!-- Info lines (right side, suggest text without being text) -->
+  <rect x="78" y="36" width="24" height="4" rx="1" fill="#58a6ff"/>
+  <rect x="78" y="48" width="20" height="3" rx="1" fill="#30363d"/>
+  <rect x="78" y="56" width="24" height="3" rx="1" fill="#30363d"/>
+  <rect x="78" y="64" width="18" height="3" rx="1" fill="#30363d"/>
+  <!-- Lock icon (security indicator) -->
+  <rect x="82" y="84" width="16" height="12" rx="1.5" fill="#3fb950"/>
+  <path d="M85 84 V79 A5 5 0 0 1 95 79 V84" fill="none" stroke="#3fb950" stroke-width="2.5" stroke-linecap="round"/>
+  <circle cx="90" cy="90" r="1.5" fill="#0d1117"/>
+</svg>