fix: Compare - degrade-routines on MariaDB 1558 + dark-mode dropdowns (#218, #219)

[EVWorth]

What

Two related Compare-feature bugs landed together:

#	Bug	Fix
#218	Compare dropdowns render white in dark mode; Source/Target labels nearly invisible	color-scheme on theme blocks; dark muted text contrast bump; disabled-state opacity rebalance
#219	Compare fails entirely against MariaDB with stale mysql.proc (error 1558), even though tables/views/triggers would have diffed fine	Routines fetch split out into its own try/catch per side + structured warning + opt-out toggle

Why together

Both bugs surface in the Compare UI in the same place. Knocked out back-to-back while context was fresh.

#218 details

src/styles/globals.css:

• Add color-scheme: dark to dark theme block. Add color-scheme: light to light theme block. Without these, Chromium uses the OS color scheme for native form controls (selects, scrollbars), so dropdown triggers + option popups + scrollbars render light even on a dark-themed page.
• Bump --color-text-muted dark from #5a5a6e to #8b8ba0. Was failing WCAG AA against the dark panel background; "Source" / "Target" labels were effectively invisible.

src/components/compare/SchemaCompare.tsx EndpointSelector:

• Label: text-[var(--color-text-muted)] -> text-[var(--color-text-secondary)]. Extra readability margin independent of the global token bump.
• Database select: disabled:opacity-40 -> disabled:text-[var(--color-text-muted)] disabled:opacity-70. With pure opacity-40 on top of an already-low-contrast placeholder, "Select database..." was nearly invisible until a connection was picked.

#219 details

src/components/compare/SchemaCompare.tsx:

• Split getRoutines out of the main Promise.all into its own try/catch. Per-side routine failures no longer cascade into a total failure. Schema diff (tables, views, triggers) now completes.

• New RoutineIssue discriminated union ({ kind: 'routines-mariadb-upgrade' | 'routines-failed', side, raw }). classifyRoutinesError() matches the substring 1558 | mysql.proc | mariadb-upgrade and tags the issue for the structured UI.

• New RoutineIssueBanner component renders the issue in a yellow alert with an action path. The MariaDB-upgrade case shows the exact mariadb-upgrade -u root -p command. The generic case shows the truncated raw error. Each banner has a dismiss X.

• "Include routines" checkbox (default on) added to the setup row. Unchecking it skips the getRoutines call entirely. Useful as an opt-out when the server's mysql.proc is broken and the user only wants to diff tables/views/triggers.

• handleCompare accumulates per-side routine errors onto a dedicated routineIssues state and renders them below the setup row. The existing "Comparison failed" red banner remains for non-routine failures (backward-compatible).

Tests added (compare 19 -> 24)

• defaults Include routines to checked
• completes comparison and shows MariaDB-upgrade warning when getRoutines throws 1558
• red "Comparison failed" banner still renders for non-routine failures (backward compat)
• routine warning dismisses via its X
• Include routines unchecked skips getRoutines call entirely

Verification

Gate	Result
npx vitest run src/components/compare/__tests__	2 files / 24 tests pass (was 19)
npx vitest run (full)	77 files / 1458 tests pass (was 1453)
npm run type-check	0 errors
npx eslint (touched files)	0 errors
npx dprint check	clean
Lefthook pre-commit (all 7 commands)	all green

Notes

• Storage of routine issue uses an array (routineIssues) rather than a single string | null. Two issues (source + target) can coexist. Dismiss is per-issue via array index filter.
• The CSV/JSON/SQL backend-rust side of routines (src-tauri/crates/mas-core/src/schema/inspector.rs:get_routines) is unchanged - this is purely a frontend UX fix.
• Out-of-scope follow-up (mentioned in fix: Compare fails entirely on MariaDB 1558 ("mysql.proc column count wrong") — routines fetch should degrade gracefully #219): enriching CoreError::Schema to carry structured sqlx error codes through IPC. Crosses the IPC contract; filing as a separate issue if pursued.

Resolves #218, #219.