chore: remove stale agent reports and add PYTHONDONTWRITEBYTECODE export to Makefile

Delete four stale SEO and style agent report JSON/MD files from agents/reports/ that had zero findings or were superseded. Export PYTHONDONTWRITEBYTECODE=1 in the Makefile so all make targets suppress bytecode generation, and add a `tree` target that lists the repository file tree via git ls-tree. Update AGENTS.md and CLAUDE.md documentation to reflect that routers now form a directory tree mirroring URL paths and that bytecode writing is disabled project-wide.

Makefile

@@ -7,6 +7,9 @@ LOCUST_SPAWN_RATE ?= 5
 LOCUST_RUN_TIME ?= 120s
 DEVPLACE_RATE_LIMIT ?= 1000000
 
+PYTHONDONTWRITEBYTECODE := 1
+export PYTHONDONTWRITEBYTECODE
+
 .PHONY: install dev clean test test-headed coverage coverage-headed coverage-html locust locust-headless
 
 install:
@@ -18,6 +21,9 @@ dev:
 prod:
 	DEVPLACE_WEB_WORKERS=2 uvicorn devplacepy.main:app --host 0.0.0.0 --port 10500 --workers 2 --backlog 8192 --proxy-headers --forwarded-allow-ips '*'
 
+tree:
+	git ls-tree --name-only -r -t HEAD | sort | awk -F/ '{for(i=1;i<NF;i++) printf "  "; print $$NF}'
+
 test:
 	PLAYWRIGHT_HEADLESS=1 python -m pytest tests/ -x