feat: rename to FabledScryer, multi-dashboard system, plugin management, branding

- Rename package fablednetmon → fabledscryer throughout
- Multi-dashboard: ownership, per-user defaults, HTMX edit (add/remove/reorder)
- Read-only share tokens scoped to individual dashboards
- Dashboard edit is HTMX-driven (no page reloads)
- Plugin management system: remote catalog, download/install, hot-reload, in-app restart
- plugin_index.py: fetch/cache remote index.yaml; default URL → bvandeusen/fabledscryer-plugins
- plugin_manager.py: download_and_install_plugin, hot_reload_plugin, restart_app
  - ZIP extraction handles GitHub archive formats (name-v1.0.0/, name-main/)
- Settings split into tabbed sections: General, Notifications, Ansible, Plugins
- Plugins tab: catalog browser (HTMX), install/activate/update/restart actions
- UI/branding: dark palette (#07071a), crystal ball SVG logo, animated star field,
  Libertinus Serif applied to headings, nav, labels, and section titles
- Widget registry (core/widgets.py) for dashboard plugin integration
- UPS widget.html (dashboard card) and settings/_tabs.html include
- Migrations 0005–0008: dashboards, is_default, ownership, share tokens
- docs/plugins/: writing-a-plugin.md updated with publishing guide,
  index.yaml.example template for fabledscryer-plugins repo

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

fabledscryer/migrations/versions/0008_share_tokens.py

@@ -0,0 +1,41 @@
+"""Dashboard share tokens
+
+Revision ID: 0008_share_tokens
+Revises: 0007_dashboard_ownership
+Create Date: 2026-03-22
+"""
+from typing import Sequence, Union
+from alembic import op
+import sqlalchemy as sa
+
+revision: str = "0008_share_tokens"
+down_revision: Union[str, None] = "0007_dashboard_ownership"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "dashboard_share_tokens",
+        sa.Column("id", sa.Integer, primary_key=True, autoincrement=True),
+        sa.Column("dashboard_id", sa.Integer,
+                  sa.ForeignKey("dashboards.id", ondelete="CASCADE"), nullable=False),
+        sa.Column("token_hash", sa.String(64), nullable=False, unique=True),
+        sa.Column("label", sa.String(128), nullable=False, server_default=""),
+        sa.Column("expires_at", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("created_by", sa.String(36),
+                  sa.ForeignKey("users.id", ondelete="SET NULL"), nullable=True),
+        sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
+    )
+    op.create_index(
+        "ix_share_tokens_dashboard_id", "dashboard_share_tokens", ["dashboard_id"],
+    )
+    op.create_index(
+        "ix_share_tokens_hash", "dashboard_share_tokens", ["token_hash"],
+    )
+
+
+def downgrade() -> None:
+    op.drop_index("ix_share_tokens_hash", "dashboard_share_tokens")
+    op.drop_index("ix_share_tokens_dashboard_id", "dashboard_share_tokens")
+    op.drop_table("dashboard_share_tokens")