feat: Add telemetry endpoint for tracking active Neovim session via FocusGained

gemini_telemetry.lua

@@ -0,0 +1,28 @@
+local function send_telemetry(event)
+    local session_id = vim.v.servername
+    if not session_id or session_id == '' then return end
+    
+    local file = vim.api.nvim_buf_get_name(0)
+    local row, col = unpack(vim.api.nvim_win_get_cursor(0))
+    
+    local payload = string.format(
+        '{"session_id": "%s", "event": "%s", "file": "%s", "line": %d, "col": %d}',
+        session_id:gsub("\\", "\\\\"), event, file:gsub("\\", "\\\\"), row, col
+    )
+    
+    vim.fn.jobstart({
+        "curl", "-s", "-X", "POST", "http://127.0.0.1:3000/nvim/telemetry",
+        "-H", "Content-Type: application/json",
+        "-d", payload
+    }, { detach = true })
+end
+
+local group = vim.api.nvim_create_augroup("GeminiTelemetry", { clear = true })
+
+local events = { "FocusGained", "BufEnter", "VimEnter" }
+for _, event in ipairs(events) do
+    vim.api.nvim_create_autocmd(event, {
+        group = group,
+        callback = function() send_telemetry(event) end
+    })
+end