Reorganize brain: projects/ top level, rename filenames, update homepage

- Moved everything from ideas/passepartout/ to projects/passepartout/
- Moved legal structures to projects/flags/
- Created missing _index.org files for all subdirectories
- Stripped redundant passepartout- prefix from filenames
- Rewrote root _index.org as generalized brain index (projects + concepts)
- Updated Hugo nav to Projects/Concepts
- Updated build script section descriptions
- Deleted stale ideas/passepartout-economics.md orphan

projects/passepartout/architecture/_index.org

@@ -0,0 +1,30 @@
+:PROPERTIES:
+:CREATED:  [2026-05-24 Sun]
+:ID:       5e7f1d2a-3b4c-5d6e-7f8a-9b0c1d2e3f4a
+:END:
+#+title: Passepartout — Architecture Section Index
+#+filetags: :passepartout:index:
+
+This section documents the Passepartout architecture: the staged build-out from conventional computing through verified infrastructure, the subsystems, and the systemic effects of verification becoming the default.
+
+**Architecture overviews:**
+- [[id:1c3ec48b-446c-50d2-b53e-126a81f5143f][Architecture index]] — Passepartout architecture, market, revenue paths
+- [[id:a1fac32a-47de-5fbd-b67d-29152c851747][Architecture overview]] — the three subsystems at a glance
+- [[id:42c86e6f-4f27-4993-8238-b7bc7d15fb7b][Environment subsystem]] — the Lisp image, editor, browser, shell, hardware
+
+**Staged roadmap (progressive capability layers):**
+Each stage covers: what is added, what threats are eliminated, what it costs, when it is viable.
+
+| Stage | Delivers | Key cost | Timeline |
+|-------+----------+----------+----------|
+| [[id:4a1f23b0-abc1-4def-9876-543210abcdef][0 — Now]] | Baseline: conventional computing | Patching treadmill, no deductive guarantees | Today |
+| [[id:4a1f23b0-abc2-4def-9876-543210abcdef][1 — Social Protocol]] | Communication integrity, provable DAG | Crypto overhead, key management | Today |
+| [[id:4a1f23b0-abc3-4def-9876-543210abcdef][2 — Verification]] | Verified gate, capability auth | Policy formalization burden | Today (limited) |
+| [[id:4a1f23b0-abc4-4def-9876-543210abcdef][3 — Lisp Machine]] | Lisp image, Merkle memory, no kernel | Lisp tax, no backward compat, single address space | 2-5yr (soft) / 5-10yr (ASIC) |
+| [[id:4a1f23b0-abc5-4def-9876-543210abcdef][4 — Inference]] | In-process LLM, token interception | ~10x compute/RAM/storage | Server now; consumer 3-5yr |
+| [[id:4a1f23b0-abc6-4def-9876-543210abcdef][5 — Weights]] | Plist-native weights, weight-level provenance | ~100x GPU / ~2-5x ASIC | GPU hybrid now; ASIC 5-10yr |
+| [[id:4a1f23b0-abc7-4def-9876-543210abcdef][6 — Training]] | Verified fine-tuning, neural world model | ~100x fine-tuning only | 3-5yr fine-tuning |
+| [[id:4a1f23b0-abc8-4def-9876-543210abcdef][7 — Remaining]] | Physical threats, oracles, speculation, bootstrap axiom | Mitigations are non-computational | Forever |
+
+**Systemic analysis:**
+- [[id:b9fa4b7b-bc61-4d7f-918d-ff687b80f2ba][Systemic effects over time]] — how verification cascades across society, economics, and geopolitics