Cut non-essential prose from docs and comments, and require the same of every future change

README loses the competitor comparison, the personas and the repeated philosophy; the
five near-identical E2E command blocks become a table plus one command, and the file
map a clause per entry. AGENTS.md keeps every decision but drops the narrative around
them. todo.md's completed items collapse to their task line — git holds the rest.

Comments lose restatement, README duplication and history ("used to", "originally",
dated notes). AGENTS.md gains a Prose discipline section making this a standing pass on
every change rather than a one-off cleanup.

src/compose.test.ts now expects 6 documented E2E run commands, not 10, since the README
states the command once instead of per suite.

src/auth/routes.ts

@@ -231,10 +231,8 @@ function logout(kratos: KratosPublic, secureCookies: boolean): BuiltinRoute["han
 }
 
 // Kratos' self-service error sink (kratos.yml flows.error.ui_url → /error). A flow that fails a
-// security/expiry check redirects the browser here with ?id=<uuid>. Render a themed page with a
-// path back into sign-in instead of the catch-all 404 ("Page not found") it used to hit. The
-// canonical-host redirect prevents the common cause (a lost cross-host CSRF cookie); this is the
-// honest fallback for any genuine flow error. The id is shown only for support reference.
+// security/expiry check redirects the browser here with ?id=<uuid>; render a themed page with a
+// path back into sign-in rather than the catch-all 404. The id is shown for support reference only.
 const errorSink = (ctx: RequestContext): RouteResult =>
   ({ data: { id: ctx.url.searchParams.get("id") }, view: "error" });