feat: add markdown opt-in extra + fix local.lua load order

Adds lua/whipsmart/plugins/markdown.lua as an opt-in extra that bundles
render-markdown.nvim (unconditional) and obsidian.nvim + blink.compat
(gated on vim.g.obsidian_vaults being set in local.lua). Uses
blink.cmp.config.merge_with to extend the completion config post-setup
with markdown-specific per_filetype sources and [[wikilink trigger behaviour.

Also fixes a load-order bug where pcall(require, 'local') ran before
vim.g.have_nerd_font and all vim.o.* defaults were set, making it
impossible for local.lua to override them. The call is now at the end
of Section 1 so local.lua runs last and overrides work correctly.

UNIFIED.md updated: markdown extra documented, roci migration and
load-order fix checked off the roadmap.

UNIFIED.md

@@ -31,7 +31,17 @@ require 'whipsmart.plugins.debug'
 ```
 
 Available extras: `autopairs`, `debug` (DAP/Go), `gitsigns` (extended keymaps),
-`indent_line`, `lint`, `neo-tree`.
+`indent_line`, `lint`, `markdown` (render-markdown + obsidian), `neo-tree`.
+
+The `markdown` extra reads `vim.g.obsidian_vaults` from `local.lua` to configure
+obsidian.nvim; render-markdown loads unconditionally. Example `local.lua` snippet:
+```lua
+vim.g.obsidian_vaults = { { name = 'personal', path = '~/Obsidian/Main' } }
+```
+Then activate in `lua/custom/plugins/markdown.lua`:
+```lua
+require 'whipsmart.plugins.markdown'
+```
 
 ## 💻 Per-Machine Local Config
 Each machine maintains a `lua/local.lua` that is **gitignored** and never committed.
@@ -60,6 +70,9 @@ cp ~/.config/nvim/lua/local.lua.example ~/.config/nvim/lua/local.lua
 - [x] Document LSP server setup and opt-in extras workflow.
 - [x] Replace hostname detection with gitignored lua/local.lua per-machine overrides.
 - [x] Port hecate config: LSP servers, formatters, treesitter parsers, custom plugins.
+- [x] Fix `local.lua` load order — `pcall(require, 'local')` moved to end of Section 1 so it can override defaults.
+- [x] Add markdown opt-in extra (render-markdown, obsidian, blink.compat).
+- [x] Migrate roci to whipsmart.
 - [ ] Migrate vera and tau to whipsmart (create their lua/local.lua files).
 - [ ] Add machine-specific UI toggles for terminal vs. GUI Neovim (via local.lua).
 - [ ] Centralize snippet collections.

init.lua

@@ -47,11 +47,6 @@ do
   vim.g.mapleader = ' '
   vim.g.maplocalleader = ' '
 
-  -- [[ Machine Specific Setup ]]
-  -- lua/local.lua is gitignored — each machine maintains its own copy.
-  -- See lua/local.lua.example for available options.
-  pcall(require, 'local')
-
   -- Set to true if you have a Nerd Font installed and selected in the terminal
   vim.g.have_nerd_font = true
 
@@ -118,6 +113,12 @@ do
     group = vim.api.nvim_create_augroup('whipsmart-highlight-yank', { clear = true }),
     callback = function() vim.hl.on_yank() end,
   })
+
+  -- [[ Machine Specific Setup ]]
+  -- lua/local.lua is gitignored — each machine maintains its own copy.
+  -- Loaded last so it can override any default set above.
+  -- See lua/local.lua.example for available options.
+  pcall(require, 'local')
 end
 
 -- ============================================================

lua/whipsmart/plugins/markdown.lua

@@ -0,0 +1,84 @@
+local function gh(repo) return 'https://github.com/' .. repo end
+
+-- ── render-markdown (always loaded) ─────────────────────────────────────────
+vim.pack.add {
+  gh 'MeanderingProgrammer/render-markdown.nvim',
+  gh 'nvim-treesitter/nvim-treesitter',
+}
+
+require('render-markdown').setup {
+  render_modes = { 'n', 'c' },
+  heading  = { enabled = true },
+  bullet   = { enabled = true },
+  checkbox = { enabled = true },
+  code     = { enabled = true },
+}
+
+vim.api.nvim_create_autocmd('FileType', {
+  desc = 'Markdown editing options',
+  group = vim.api.nvim_create_augroup('whipsmart-markdown', { clear = true }),
+  pattern = 'markdown',
+  callback = function()
+    vim.opt_local.wrap = true
+    vim.opt_local.linebreak = true
+    vim.opt_local.spell = true
+    vim.opt_local.spelllang = 'en_us'
+    vim.opt_local.conceallevel = 2
+  end,
+})
+
+-- ── obsidian (opt-in — requires vim.g.obsidian_vaults to be set in local.lua) ─
+-- Example local.lua entry:
+--   vim.g.obsidian_vaults = { { name = 'personal', path = '~/Obsidian/Main' } }
+if not vim.g.obsidian_vaults then return end
+
+-- blink.compat must be unversioned (HEAD) — released tags lack cmp.get_config()
+vim.pack.add {
+  { src = gh 'epwalsh/obsidian.nvim', version = vim.version.range '*' },
+  gh 'nvim-lua/plenary.nvim',
+  gh 'saghen/blink.compat',
+}
+
+require('blink.compat').setup {}
+
+require('obsidian').setup {
+  workspaces = vim.g.obsidian_vaults,
+  completion = { nvim_cmp = false, min_chars = 2 },
+}
+
+-- Register obsidian nvim-cmp sources via blink.compat shim
+local cmp = require 'cmp'
+cmp.register_source('obsidian',      require('cmp_obsidian').new())
+cmp.register_source('obsidian_new',  require('cmp_obsidian_new').new())
+cmp.register_source('obsidian_tags', require('cmp_obsidian_tags').new())
+
+-- Extend blink.cmp config post-setup via the v1 merge_with API.
+-- Called from custom/plugins/ (Section 3), so plugins.cmp has already run setup().
+require('blink.cmp.config').merge_with {
+  completion = {
+    trigger = {
+      -- Remove '[' so [[ wikilinks trigger the completion menu
+      show_on_x_blocked_trigger_characters = { "'", '"', '(', '{' },
+    },
+    menu = {
+      -- Suppress auto-popup in markdown/text except when '[' was the trigger
+      auto_show = function(ctx)
+        if vim.tbl_contains({ 'markdown', 'text' }, vim.bo.filetype) then
+          return ctx.trigger.initial_kind == 'trigger_character'
+            and ctx.trigger.initial_character == '['
+        end
+        return true
+      end,
+    },
+  },
+  sources = {
+    per_filetype = {
+      markdown = { 'obsidian', 'obsidian_new', 'obsidian_tags', 'lsp', 'path', 'snippets', 'buffer' },
+    },
+    providers = {
+      obsidian      = { name = 'obsidian',      module = 'blink.compat.source' },
+      obsidian_new  = { name = 'obsidian_new',  module = 'blink.compat.source' },
+      obsidian_tags = { name = 'obsidian_tags', module = 'blink.compat.source' },
+    },
+  },
+}