docs: replace model experience tables with sections

packages/llm/llm/README.md

@@ -50,10 +50,17 @@ Two adapters implement `LlmAdapter` against this vocabulary, deliberately built
 
 ## Model Experience
 
-| Context surface | What the model sees | Token effect |
-|---|---|---|
-| Provider request transport | This service adds no system text, schema, or message. It routes the already-assembled frozen `GenerateOptions` to one adapter, while `llm/stream` listeners may cache, retry, or replace the stream without mutating that request. | Zero direct context tokens. The selected adapter and provider tokenizer determine billing, cache accounting, and serialization overhead for the existing content. |
-| Streamed model output | Text, reasoning, and tool-call chunks are exposed to the loop, which decides what becomes retained assistant history. | Output usage is provider-reported; later input cost arises only after the loop records assembled content. |
+### Provider request transport
+
+**What the model sees**: This service adds no system text, schema, or message. It routes the already-assembled frozen `GenerateOptions` to one adapter, while `llm/stream` listeners may cache, retry, or replace the stream without mutating that request.
+
+**Token effect**: Zero direct context tokens. The selected adapter and provider tokenizer determine billing, cache accounting, and serialization overhead for the existing content.
+
+### Streamed model output
+
+**What the model sees**: Text, reasoning, and tool-call chunks are exposed to the loop, which decides what becomes retained assistant history.
+
+**Token effect**: Output usage is provider-reported; later input cost arises only after the loop records assembled content.
 
 ## Known Limitations and Deferred Work