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/src/service-worker/vault.ts

@@ -30,8 +30,8 @@ export interface VaultMeta {
 
 /// Read the vault salt and KDF params from the git repo.
 export async function fetchVaultMeta(git: GitHost): Promise<VaultMeta> {
-  const saltBytes = await git.readFile('.idfoto/salt');
-  const paramsRaw = await git.readFile('.idfoto/params.json');
+  const saltBytes = await git.readFile('.relicario/salt');
+  const paramsRaw = await git.readFile('.relicario/params.json');
   const paramsJson = new TextDecoder().decode(paramsRaw);
   return { salt: saltBytes, paramsJson };
 }