[idea] Add gitsigns hunk stats (+/~/−) to the statusline git section #170

What

Extend the statusline's git branch component to also show the buffer's hunk counts — added, changed, and removed lines — using data already provided by gitsigns.

Where

lua/config/statusline.lua — current_git_branch() function, lines 28–38:

local function current_git_branch()
    local branch = vim.b.gitsigns_head
    if not branch or branch == "" then return "" end
    return " %#Git#  " .. branch .. " " .. "%*"
end

Why it matters

gitsigns already exposes b:gitsigns_status_dict (with .added, .changed, .removed integer fields) on every buffer it tracks. The statusline currently shows the branch name but no indication of whether the buffer has local changes or how large they are. Adding +2 ~1 -0 next to the branch name makes that visible at a glance without opening diffview or running git status.

Fits naturally with the existing diagnostic count display ( N┊ N┊…) — same "counts at a glance" philosophy.

Suggested implementation

local function current_git_branch()
    local ok, _ = pcall(require, "gitsigns")
    if not ok then return "" end
    local branch = vim.b.gitsigns_head
    if not branch or branch == "" then return "" end
    local stats = vim.b.gitsigns_status_dict
    local diff = ""
    if stats then
        if (stats.added   or 0) > 0 then diff = diff .. " +" .. stats.added   end
        if (stats.changed or 0) > 0 then diff = diff .. " ~" .. stats.changed  end
        if (stats.removed or 0) > 0 then diff = diff .. " -" .. stats.removed  end
    end
    return " %#Git#  " .. branch .. diff .. " %*"
end

Optional: use separate highlight groups for each sign (green +, yellow ~, red -) to match the sign-column colours.