refactor(session,pdf): simplify git perms + rich text PDF

- claude_session: replace 10 individual git command patterns with single Bash(git *) wildcard
- generate_pdf: add italic/bold-oblique font loading and render_rich_text() for inline bold/italic

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/claude_session.py

@@ -53,15 +53,7 @@ _DEFAULT_ALLOWED_TOOLS = [
     "WebFetch", "WebSearch",
     "Bash(python3 *)", "Bash(.venv/bin/python3 *)",
     "Bash(pip *)", "Bash(pytest *)",
-    "Bash(git add *)", "Bash(git commit *)",
-    "Bash(git push)", "Bash(git push *)",
-    "Bash(git pull)", "Bash(git pull *)",
-    "Bash(git status)", "Bash(git status *)",
-    "Bash(git diff)", "Bash(git diff *)",
-    "Bash(git log)", "Bash(git log *)",
-    "Bash(git checkout *)",
-    "Bash(git branch)", "Bash(git branch *)",
-    "Bash(git stash)", "Bash(git stash *)",
+    "Bash(git *)",
     "Bash(npm *)", "Bash(node *)", "Bash(npx *)",
     "Bash(systemctl --user *)",
     "Bash(trash *)", "Bash(mkdir *)", "Bash(cp *)",