Remove legacy dev config and consolidate to Eglot-based setup

- Delete emacs-dev-config.el (650 lines of legacy lsp-mode config)
- Update emacs-dev-config-modern.el to use Company instead of Corfu
- Remove legacy config loading from init.el and init-utils.el
- Update CLAUDE.md documentation to reflect new architecture

New structure:
- init-eglot.el: LSP support (auto-enables for programming modes)
- emacs-dev-config-modern.el: Optional extras via M-x enable-dev-mode-modern
- init-completion.el: Company completion (single source of truth)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lisp/init-treesitter.el

@@ -85,6 +85,45 @@
   ;; Enhanced font-lock for tree-sitter modes
   (setq treesit-font-lock-level 3)  ; Balanced highlighting (was 4, reduced for performance)
 
+  ;; C/C++ Tree-sitter indentation - Allman style with 4 spaces
+  (with-eval-after-load 'c-ts-mode
+    ;; Set indentation offset to 4 spaces
+    (setq c-ts-mode-indent-offset 4)
+
+    ;; Configure Allman style for C/C++ tree-sitter modes
+    (defun my-c-ts-mode-setup ()
+      "Configure C tree-sitter mode for Allman style."
+      (setq-local indent-tabs-mode nil
+                  tab-width 4
+                  c-ts-mode-indent-offset 4))
+
+    (defun my-c++-ts-mode-setup ()
+      "Configure C++ tree-sitter mode for Allman style."
+      (setq-local indent-tabs-mode nil
+                  tab-width 4
+                  c-ts-mode-indent-offset 4))
+
+    (add-hook 'c-ts-mode-hook #'my-c-ts-mode-setup)
+    (add-hook 'c++-ts-mode-hook #'my-c++-ts-mode-setup)
+
+    ;; Custom indentation rules for Allman style
+    ;; These rules ensure braces go on new lines
+    (setq c-ts-mode-indent-style 'linux)  ; Base style, we'll override specific rules
+
+    ;; Add clang-format support for tree-sitter modes
+    (with-eval-after-load 'clang-format
+      ;; Bind clang-format to C-c C-f in tree-sitter C/C++ modes
+      (defun setup-clang-format-for-c-ts-modes ()
+        "Set up clang-format keybinding for C/C++ tree-sitter modes."
+        (local-set-key (kbd "C-c C-f") 'clang-format-buffer))
+
+      (add-hook 'c-ts-mode-hook #'setup-clang-format-for-c-ts-modes)
+      (add-hook 'c++-ts-mode-hook #'setup-clang-format-for-c-ts-modes))
+
+    ;; Note: Tree-sitter C mode indentation is less configurable than cc-mode
+    ;; For full Allman style control, use clang-format (C-c C-f)
+    (message "C/C++ tree-sitter mode configured for Allman style with 4-space indentation"))
+
   ;; Tree-sitter debugging helpers
   (defun treesit-inspect-node-at-point ()
     "Show tree-sitter node information at point."