Stacked on #84 .

This PR gives us the ability to apply tags using rules. Manual tag removals are remembered and not reapplied.

--- 🤖 Generated with Claude Code

Tag rules with sticky removals

Adds a tag-rule engine that automatically applies tags to transactions, mirroring the existing category/name rule patterns. Rules match by transaction name, regex, or match-all — where match-all + an account scope gives you the "tag everything in this account" default-tag use case.

What it does

• New rule types: name (case-insensitive substring), regex (against name + merchant), and all (every transaction in scope). Each rule can be scoped to an account and gated by an amount range.
• Backfill + ongoing apply: rules backfill matching transactions on save, and re-apply to new rows on Plaid sync and CSV import.
• Sticky removals: removing a tag from a transaction is permanent. removeTagFromTransaction records a suppression so no rule — existing or created later — re-adds that tag. The only undo is manually re-adding the tag, which clears the suppression.
• Live match count: the rule editor (TUI + GUI) shows how many transactions a rule will match as you build it, so a global match-all rule is never a surprise.
• Full TUI + GUI parity — new "Tag rules" tab/section in both Rules screens.

Why suppressions

Unlike category stickiness (which can COALESCE over a single manual_category column), tags are many-to-many with no single column to override. A dedicated tag_rule_suppressions table records intentional removals so re-running rules can't undo a user's deliberate choice. All removal paths (TUI, GUI, agent tool) funnel through removeTagFromTransaction, so the guarantee holds at one chokepoint.

Schema

Two new tables (created via CREATE TABLE IF NOT EXISTS):

• tag_rules — priority, match_type ('name'|'regex'|'all'), pattern, tag_id, account_id, min_amount, max_amount
• tag_rule_suppressions — (transaction_id, tag_id) PK

Notable files

• core/tag-rules.ts (new) — loadTagRules, tagRuleMatches, applyTagRules, countTagRuleMatches
• core/tags.ts — suppression hooks on add/remove; deleteTag clears a tag's rules + suppressions
• core/rules.ts — saveTagRule / deleteTagRule
• core/sync.ts, core/accounts.ts — apply rules to newly synced/imported rows
• tui/Rules.tsx, gui/renderer/src/screens/Rules.tsx — UI parity

Testing

• 14 new tests in tests/tag-rules.test.ts covering matching (name/regex/all/account/amount), backfill, no-double-count on re-run, stickiness (removed-stays-gone, removal-before-rule, manual-readd-clears), and rule/tag lifecycle.
• TUI screen tests updated for the new tab; full suite (664 tests) and both typechecks pass.