feat: add blink.cmp and disable custom completion pipeline

lua/core/keymap.lua

@@ -99,9 +99,7 @@ vim.keymap.set("n", "gr", "<Nop>")
 vim.cmd.aunmenu({ "PopUp.-1-" })
 vim.cmd.aunmenu({ "PopUp.How-to\\ disable\\ mouse" })
 
--- Insert-mode Emacs bindings
-vim.keymap.set("i", "<C-f>", "<Right>")
-vim.keymap.set("i", "<C-b>", "<Left>")
+-- Insert-mode Emacs bindings (C-f/C-b live further down inside hover_scroll_map)
 vim.keymap.set("i", "<C-a>", "<C-o>^")
 vim.keymap.set("i", "<C-e>", function()
     -- Fall through to Vim's default (close popup + revert) during completion.
@@ -160,8 +158,43 @@ vim.keymap.set("n", "K", function()
     vim.lsp.buf.hover({ max_width = 80 })
 end)
 vim.keymap.set({ "i", "s" }, "<C-s>", function()
+    local winid = vim.b.lsp_floating_preview
+    if winid and vim.api.nvim_win_is_valid(winid) then
+        vim.api.nvim_win_close(winid, false)
+        return
+    end
     vim.lsp.buf.signature_help({ max_width = 80 })
 end)
+
+---@param mode string | string[]
+---@param key string
+---@param direction "up" | "down"
+---@param count integer
+---@param fallback? string
+local function hover_scroll_map(mode, key, direction, count, fallback)
+    vim.keymap.set(mode, key, function()
+        local winid = vim.b.lsp_floating_preview
+        if not winid or not vim.api.nvim_win_is_valid(winid) then
+            return fallback or key
+        end
+        vim.schedule(function()
+            local scroll_key = direction == "down" and vim.keycode("<C-e>")
+                or vim.keycode("<C-y>")
+            vim.api.nvim_win_call(winid, function()
+                vim.cmd.normal({
+                    args = { count .. scroll_key },
+                    bang = true,
+                })
+            end)
+        end)
+        return ""
+    end, { expr = true, replace_keycodes = true })
+end
+hover_scroll_map({ "n", "s" }, "<C-f>", "down", 5)
+hover_scroll_map({ "n", "s" }, "<C-b>", "up", 5)
+hover_scroll_map("i", "<C-f>", "down", 5, "<Right>")
+hover_scroll_map("i", "<C-b>", "up", 5, "<Left>")
+
 ---@param key string
 ---@param dir 1 | -1
 local function snippet_jump_map(key, dir)
@@ -174,6 +207,7 @@ local function snippet_jump_map(key, dir)
 end
 snippet_jump_map("<Tab>", 1)
 snippet_jump_map("<S-Tab>", -1)
+
 vim.keymap.set({ "n", "i" }, "<C-h>", vim.lsp.buf.document_highlight)
 vim.keymap.set({ "n", "x" }, "<leader>lf", vim.lsp.buf.format)
 vim.keymap.set("n", "grl", function()