feat: UI modernization — Manrope font, dark/light theme, card-based layouts

- Add Manrope as primary UI font via Google Fonts (wiregui/pages/style.py)
- Add dark/light/auto theme toggle in header, persisted to users.theme_preference
- Alembic migration for theme_preference column
- Redesign account page with card-based layout matching admin pages
- Convert settings page from tabs to stacked cards
- Replace all outline buttons with solid unelevated buttons
- Fix dark mode: remove hardcoded bg-grey-1/text-grey-7, use theme-safe colors
- Fix CI: add ca-certificates to release job for SSL cert verification
- Add no-coauthor and commit conventions to CLAUDE.md

alembic/versions/a3f1d8e92b01_add_theme_preference_to_users.py

@@ -0,0 +1,27 @@
+"""add theme_preference to users
+
+Revision ID: a3f1d8e92b01
+Revises: 0741bc76e748
+Create Date: 2026-03-30 22:00:00.000000
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'a3f1d8e92b01'
+down_revision: Union[str, None] = '0741bc76e748'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column('users', sa.Column('theme_preference', sqlmodel.sql.sqltypes.AutoString(), nullable=False, server_default='auto'))
+
+
+def downgrade() -> None:
+    op.drop_column('users', 'theme_preference')