docs/ als ausgelieferter Hintergrund-Ort; Decision-Seiten bleiben in kb/, Decay-Skip fuer concept_type: decision (4.3.0, #38)

Files changed:
- AGENTS.md
- CHANGES.md
- VERSION
- instructions/kb-profiles.md
- kb/CONVENTIONS.md
- kb/concepts/COLLECTION.md
- tools/CONTRACT.md
- tools/chemenu/commands/confidence_decay.py
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/tests/test_confidence_decay.py
- tools/chemenu/tests/test_dist_cmd.py

AGENTS.md

@@ -82,6 +82,7 @@ What a file is called says who it is for and how it is loaded. This is a rule, n
 | `instructions/<name>.md` | Agents | By link, or on explicit request |
 | `instructions/<name>/SKILL.md` | Agents | By the harness, once published |
 | `types/<name>.md` | Agents + validator | Via `tools/wikitool types describe`. Split by `root:`: a page type-spec (`root: kb`) belongs to the instance and ships as `.template`; one describing a stack artifact ships verbatim |
+| `docs/<name>.md` | Agents and humans | By link, or on explicit request - never automatically, and never as instruction |
 | `INDEX.md` | Both | Generated - never hand-edited |
 
 A stage may carry both a `README.md` and a `CONTRACT.md`: different readers, different
@@ -89,6 +90,16 @@ documents. What it may not carry is the same content twice - a README that resta
 contract is a second copy that drifts. `docs verify` enforces the specific case that already
 happened once: no README may hold a copy of the `wikitool` command table.
 
+**`docs/` carries no normative sentence.** It holds why the stack is built the way it is -
+background a session consults in passing, not a rule it must follow. Anything that would bind
+belongs in a `CONTRACT.md` instead, which is what keeps invariant 8 intact here: `docs/` is
+never a second place a rule could live, only prose about rules that live elsewhere. That is also
+why nothing verifies its content - there is no rule in it to check. It has no frontmatter, no type, no index, no lint, no decay, no provenance, and no
+`COLLECTION.md` - which [kb/CONTRACT.md § Collections](kb/CONTRACT.md#collections) forbids
+outside `kb/` anyway, but the point holds independently: `docs/` stays a plain directory of
+prose, invisible to everything `tools/wikitool` does except `dist export`, which copies it
+verbatim. A fresh instance needs the reasoning as much as this one does.
+
 ## Personalization
 
 `USER.md` and `SOUL.md` are read at session start, if the runtime has not already injected
@@ -145,7 +156,8 @@ input       schema + compiler     output   derived (gitignored)
                   work/   tracked scratch, deleted when the run closes
 ```
 
-Alongside it, not part of it: `instructions/` (what agents are told to do) and this file.
+Alongside it, not part of it: `instructions/` (what agents are told to do), `docs/` (why the
+stack is built the way it is - see [File naming](#file-naming)), and this file.
 
 **By stage** - read the contract for the stage you are writing in: