refactor: delete stale files and consolidate .mindmodel structure

Deleted stale root-level Python files:
- main.py (unused 'Hello world' script)
- verify.py (unused table info script)
- scraper.py (unused MotionScraper class)
- scheduler.py (unused DataUpdateScheduler class)

Deleted duplicate .mindmodel root YAML files (subdirectory versions are more comprehensive):
- anti-patterns.yaml, architecture.yaml, conventions.yaml
- dependencies.yaml, domain.yaml, domain-glossary.yaml
- stack.yaml, tech-stack.yaml, workflows.yaml

Added comprehensive .mindmodel subdirectories:
- constraints/ (naming, db-schema, error-handling, types, etc.)
- patterns/ (api, architecture, database, python, streamlit, etc.)
- examples/ (code examples for each pattern)
- anti-patterns/, architecture/, conventions/, dependencies/, domain/, stack/

Updated ARCHITECTURE.md to reflect current codebase:
- Removed references to non-existent files
- Added missing files (explorer.py, explorer_helpers.py, pipeline/)
- Added directory structure documentation
- Updated tech stack to include scipy, sklearn, umap

Updated .gitignore:
- Added patterns for generated analysis files
- Added .worktrees/ pattern (was already in gitignore but dir was deleted)

Removed empty .worktrees/ directory

.mindmodel/domain/domain-glossary.yaml

@@ -0,0 +1,107 @@
+# Domain Glossary - Dutch Political Terms
+
+## Core Entities
+
+### Motion / Motie
+- Parliamentary motion submitted by MPs
+- Fields: `id`, `title`, `date`, `category`
+- MPs vote: **For** (+1), **Against** (-1), **Abstain** (0), **Absent**
+
+### MP / Kamerlid
+- Member of Parliament (Tweede Kamerlid)
+- Identified by full name (e.g., "Van Dijk, I.")
+- Has voting record, party affiliation, SVD position vector
+- Historical: `mp_party_history` tracks party changes over time
+
+### Party / Fractie
+- Political party (e.g., "GroenLinks-PvdA", "PVV", "VVD")
+- Party centroids: average SVD position of all MPs in party
+- Aliases: multiple spelling variants exist (see anti-patterns.yaml)
+
+### Vote / Stemming
+- Individual MP's vote on a motion: +1, 0, -1
+- Aggregated to compute SVD vectors
+
+---
+
+## Time & Analysis Concepts
+
+### Window / Tijdsvenster
+- Time period for analysis (annual or quarterly)
+- Values: "2023", "2023-Q1", "2024", etc.
+- SVD vectors computed per window
+- Windows can be aligned across time using Procrustes
+
+### Trajectory
+- MP's position change across multiple windows
+- Computed from `svd_vectors` + window ordering
+- Used for trend analysis in Evolution tab
+
+---
+
+## Mathematical / Algorithmic Terms
+
+### SVD Vector
+- 2D vector from Singular Value Decomposition of MP × Motion vote matrix
+- Represents MP's position in political space
+- `entity_id` in `svd_vectors`: either MP name (when individual MPs) or party name (when party-level)
+
+### Political Compass
+- 2D visualization: X-axis = Left↔Right, Y-axis = Progressive↔Conservative
+- SVD vectors mapped to compass quadrants
+- UMAP used for projection
+
+### Procrustes Alignment
+- Algorithm to align SVD vectors across time windows
+- Ensures comparable positions across years/quarters
+- Implemented via `scipy.spatial.procrustes` or scikit-learn
+
+### Centroid
+- Geometric center of a set of points
+- Party centroid = average SVD position of all MPs in that party
+- Computed from `svd_vectors` filtered by party
+
+### UMAP
+- Uniform Manifold Approximation and Projection
+- Dimensionality reduction for visualization
+- Optional dependency — graceful fallback if unavailable
+
+---
+
+## Visualization
+
+### PARTY_COLOURS
+- Dict mapping party names to hex color codes
+- Used in all Plotly charts for consistent party coloring
+- Source: `config.py` → `PARTY_COLOURS` constant
+- **Issue**: 3 separate alias dictionaries exist (no single source of truth)
+
+---
+
+## Application Pages
+
+### Home
+- Landing page with app overview
+
+### Stemwijzer (Quiz)
+- User answers questions → matched to parties
+- Thin wrapper around quiz module
+
+### Explorer (4 tabs)
+- **Motion tab**: SVD positions colored by vote on selected motion
+- **MP tab**: Individual MP trajectories across windows
+- **Party tab**: Party centroids with members as scatter
+- **Evolution tab**: How positions change over time
+
+---
+
+## Database Table Reference
+| Table | Key Fields |
+|-------|-----------|
+| `motions` | id, title, date, category |
+| `mp_votes` | mp_id, motion_id, vote |
+| `svd_vectors` | entity_id, window, vector_2d (list[2]) |
+| `party_centroids` | party, window, centroid_2d |
+| `mp_party_history` | mp_id, party, start_date, end_date |
+| `windows` | window_id, start_date, end_date, period_type |
+| `mp_trajectories` | mp_id, window, trajectory_vector |