fix(init): remove JSON minification that breaks edit-based codemods (#719)

## Summary

Removes JSON minification (`JSON.stringify(JSON.parse())`) from
`readSingleFile` and `preReadCommonFiles`. This was causing all
`package.json` edit-based codemods to fail.

### Root cause

The server's codemod-planner agent saw minified JSON (all whitespace
stripped) and generated `oldString`/`newString` edits based on it. But
`applyEdits` reads the actual file from disk (pretty-printed with
indentation). The fuzzy replacer chain can't bridge minified vs
pretty-printed JSON — it's structurally too different.

### Evidence

All three reference projects (opencode, gemini-cli, cline) read files
**raw without any content transformation**. The model always sees
exactly what's on disk. Our minification was an outlier that broke when
we switched from full-content replacement to edit-based codemods.

Fixes failures on node-express and remix test projects:
```
Applying changes failed after 4 attempts: Edit #1 failed on "package.json":
Could not find oldString in the file.
```

## Test plan

- [x] All 68 local-ops tests pass
- [x] Typecheck clean
- [x] Lint clean

Made with [Cursor](https://cursor.com)

Author: betegon

src/lib/init/local-ops.ts

@@ -80,15 +80,6 @@ function prettyPrintJson(content: string, indent: JsonIndent): string {
   }
 }
 
-/** Strip whitespace/formatting from JSON. Returns input unchanged if not valid JSON. */
-function minifyJson(content: string): string {
-  try {
-    return JSON.stringify(JSON.parse(content));
-  } catch {
-    return content;
-  }
-}
-
 /**
  * Patterns that indicate shell injection. Commands run via `spawn` (no shell),
  * so these have no runtime effect — they are defense-in-depth against command
@@ -400,10 +391,7 @@ export async function preReadCommonFiles(
       if (stat.size > MAX_FILE_BYTES) {
         continue;
       }
-      let content = await fs.promises.readFile(absPath, "utf-8");
-      if (filePath.endsWith(".json")) {
-        content = minifyJson(content);
-      }
+      const content = await fs.promises.readFile(absPath, "utf-8");
       if (totalBytes + content.length <= MAX_PREREAD_TOTAL_BYTES) {
         cache[filePath] = content;
         totalBytes += content.length;
@@ -549,10 +537,6 @@ async function readSingleFile(
       content = await fs.promises.readFile(absPath, "utf-8");
     }
 
-    if (filePath.endsWith(".json")) {
-      content = minifyJson(content);
-    }
-
     return content;
   } catch {
     return null;