fix(vscode): version-scope all overrides per Copilot review feedback

Address all 4 review comments on PR #414:

- Convert previously-unscoped overrides (serialize-javascript, flatted,
  markdown-it, qs, underscore, diff) to version-scoped form. Each now only
  applies to versions in the vulnerable range, eliminating the risk of
  forcing major-version upgrades on out-of-scope consumers.

- Bump brace-expansion v1 override target from ^1.1.13 -> ^1.1.14 (and
  trigger range to <1.1.14) so the override deterministically lands on
  the version the lockfile already resolved.

- Bump minimatch v3 override target from ^3.1.4 -> ^3.1.5 (and trigger
  range to <3.1.5) for the same deterministic-resolution reason.

- Replace blanket diff ^8.0.3 with two scoped ranges:
    diff@>=5.0.0 <5.2.2 -> ^5.2.2  (patches v5 line in place)
    diff@>=6.0.0 <8.0.3 -> ^8.0.3  (patches v6/v7 line, matches what
                                    mocha 11.7.5 already pulls in)

Validation:
- npm audit reports 0 vulnerabilities
- All 14 originally-flagged alerts remain resolved
- npm run compile, lint, pack all clean

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: vicperdana

packages/vscode-extension/package-lock.json

@@ -92,17 +92,18 @@
     "@vscode/vsce": "^3.7.1"
   },
   "overrides": {
-    "serialize-javascript": "^7.0.5",
-    "flatted": "^3.4.2",
-    "markdown-it": "^14.1.1",
-    "qs": "^6.14.2",
-    "underscore": "^1.13.8",
-    "diff": "^8.0.3",
+    "serialize-javascript@<7.0.5": "^7.0.5",
+    "flatted@<3.4.2": "^3.4.2",
+    "markdown-it@<14.1.1": "^14.1.1",
+    "qs@<6.14.2": "^6.14.2",
+    "underscore@<1.13.8": "^1.13.8",
+    "diff@>=5.0.0 <5.2.2": "^5.2.2",
+    "diff@>=6.0.0 <8.0.3": "^8.0.3",
     "ajv@<6.14.0": "^6.14.0",
     "picomatch@<2.3.2": "^2.3.2",
-    "brace-expansion@<1.1.13": "^1.1.13",
+    "brace-expansion@<1.1.14": "^1.1.14",
     "brace-expansion@>=2.0.0 <2.0.3": "^2.0.3",
-    "minimatch@<3.1.4": "^3.1.4",
+    "minimatch@<3.1.5": "^3.1.5",
     "minimatch@>=5.0.0 <5.1.8": "^5.1.8",
     "minimatch@>=9.0.0 <9.0.7": "^9.0.7"
   }