fix(config): cleanup bugs, redundancy, and add agent-friendly auto-reload

- remove broken mini.files mappings (plugin disabled; yazi is used now)
- dedupe tint.nvim spec (drop plugins/theme.lua, keep ui.lua)
- drop dead copilot cmp source + moot Supermaven symbol (Supermaven stays inline)
- remove yaml from biome formatters (biome has no yaml support)
- collapse 3x biome chain to a single biome-check pass
- remove duplicate insert-mode jk mapping
- lazy-load tailwind-tools by filetype
- diagnostics: update_in_insert = false
- untrack .nvimlog, add .gitignore
- auto-reload files changed on disk (autoread + checktime autocmds)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lua/options.lua

@@ -21,3 +21,6 @@ vim.g.neovide_scroll_animation_length = 0.15
 vim.g.neovide_cursor_animation_length = 0.11
 
 vim.o.swapfile = false
+
+-- reload files edited on disk (e.g. by coding agents); see lua/autocmds.lua for the trigger
+vim.o.autoread = true