fix(startup-banner): correct AGENTS/SKILLS/EXTENSIONS stats and add info dashboard

[aporcelli]

Problem

The startup banner HUD displays inaccurate information:

• AGENTS label counts skill-registered commands from pi.getCommands(), not actual SDD agent files
• EXTENSIONS reads settings.extensions[] which is always empty; real extensions are declared in each installed package's pi.extensions manifest
• No distinction between SDD phase agents and on-demand skills

Solution

AGENTS → AGENTS + SKILLS (split)

Before	After
AGENTS: N loaded (skill commands)	AGENTS: N phases (SDD agent files)
	SKILLS: N loaded (skill commands)

• AGENTS counts files in ~/.pi/agent/agents/sdd-*.md
• SKILLS keeps the original pi.getCommands().filter(source==="skill") count

EXTENSIONS: now counts real extension files

Scans each installed package's package.json and sums pi.extensions entries, instead of reading the always-empty settings.extensions[].

Dashboard layout (wide mode)

PATH:       /home/user/project        EXTENSIONS: N active
GIT:        On branch main            PLUGINS:    N package(s)
MCP:        N server(s)               SKILLS:     N loaded
AGENTS:     N phases                  TOOLS:      N custom
VER:        v0.75.4

Technical changes

• Added readdir import for counting SDD agent files
• Added countSddAgents() — reads ~/.pi/agent/agents/ for sdd-*.md files
• Fixed countPackageExtensions() — resolves each npm package's package.json, reads pi.extensions, sums counts. Fixed early return null bug that aborted the entire function on git packages
• Removed broken settings.extensions[] lookup
• Reordered dashboard rows: Left: PATH, GIT, MCP, AGENTS, VER | Right: EXTENSIONS, PLUGINS, SKILLS, TOOLS

Changes

File	Change
extensions/startup-banner.ts	Enhanced HUD: split AGENTS/SKILLS, fixed EXTENSIONS count, reordered layout

Test Plan

• Verified AGENTS shows correct count of sdd-*.md files in agent dir
• Verified SKILLS count matches pi.getCommands() output
• Verified EXTENSIONS matches sum of pi.extensions across installed packages
• Verified PLUGINS count matches settings.packages length
• Verified layout renders correctly in both wide and narrow terminal widths

[Alan-TheGentleman]

Thanks for the cleanup here, the direction for splitting AGENTS/SKILLS and counting real extension manifests makes sense.

I’m requesting changes because this PR also removes the existing startup gating around CLI commands and small/unsupported terminal modes. That changes behavior outside the stats/dashboard fix: the banner can clear/render during flows like pi update, pi install, scripted runs, or constrained terminals where current main intentionally skips or downgrades the intro.

Can you restore the CLI/TTY/terminal-size/resize guard semantics from current main while keeping the stats/dashboard changes? Also please remove or finish the new sparkle path, since renderStarCell() currently always returns null and leaves the sparkle variables effectively dead.