fix(panel): render country/language flags as SVG (flag-icons)

[glennjacobs]

Problem

A contributor reported the country flags on the new Inertia panel didn't render — they showed as broken glyphs instead of flags.

The flags are emoji flag characters (regional-indicator pairs, e.g. U+1F1EC U+1F1E7 for 🇬🇧). Windows ships no flag glyphs in its emoji font, so every browser on Windows falls back to a replacement/boxed glyph. macOS/iOS render them, which is why it looked fine in development.

Fix

Render flags as SVG instead of relying on the OS emoji font, via a <Flag> component backed by flag-icons — keyed by the ISO-2 codes already in the data, so they render identically on every OS.

Wired into every flag surface:

• Countries table (the reported screen)
• URL slugs language column
• Regions & tax-zones country chips and pickers (Combobox options gained an optional per-option flag)

flagForLanguage() (returned an emoji string) becomes regionForLanguage() (returns an ISO-2 region code). The one native <select> that showed an emoji in its option text (add-URL language picker) drops it — a native <option> can't hold an SVG, and plain text beats a broken glyph.

Vite base-path fix (why the SVGs still 404'd at first)

flag-icons is the first dependency to ship bundled CSS url() assets. They 404'd because the panel serves its assets from /vendor/lunar-panel/build/, but buildDirectory: 'build' baked a /build/ base into url() references. Entry CSS/JS were unaffected only because Laravel's @vite rewrites those from the manifest — CSS-internal url() can't be rewritten.

Pinned the build-time Vite base to the real serve path (dev untouched). This hardens the panel for any bundled url() asset going forward, not just flags.

Notes for reviewers

• Adds one runtime dependency: flag-icons@^7.5.0.
• <Flag> is intentionally not added to the public ui.ts add-on barrel — kept internal for now.
• Requires npm install + npm run build in packages/panel after checkout.

Verification

• vitest: 211 passed · type-check: clean · build: OK (flag SVGs emit as assets, load on demand)
• Pint: passed · panel Pest suite: 684 passed
• Confirmed rebuilt CSS references /vendor/lunar-panel/build/assets/…svg and the SVG is reachable through the asset symlink.

🤖 Generated with Claude Code