style: auto-fix ESLint issues (curly braces and formatting)

- Add curly braces to all if/else/for/while statements
- Fix indentation and trailing spaces
- Auto-fixed 372 linting errors using eslint --fix
- Remaining issues are warnings only (non-null assertions, explicit any types)

src/models/gemini.test.ts

@@ -27,12 +27,12 @@ function makeResponse(parts: unknown[], finishReason = 'STOP', usage = { promptT
       usageMetadata: usage,
       text: () => {
         const textParts = parts.filter((p: unknown) => typeof p === 'object' && p !== null && 'text' in p);
-        if (textParts.length === 0) throw new Error('No text parts');
+        if (textParts.length === 0) {throw new Error('No text parts');}
         return textParts.map((p: unknown) => (p as { text: string }).text).join('');
       },
       functionCalls: () => {
         const fcParts = parts.filter((p: unknown) => typeof p === 'object' && p !== null && 'functionCall' in p);
-        if (fcParts.length === 0) return undefined;
+        if (fcParts.length === 0) {return undefined;}
         return fcParts.map((p: unknown) => (p as { functionCall: { name: string; args: object } }).functionCall);
       },
     },