Add the assembler that folds streamed chunks into a completion

Implemented-By: GLM-5.3 (z.ai, default settings) via OpenCode

docs/implementer-log.md

@@ -20,6 +20,7 @@ reviewer adds findings under "Reviews" once per milestone.
 | M2a/04-loopd-http | 2026-09-18 | done | 2 | fail | none | Added `pub mod http;` to crates/loopd/src/lib.rs and wrote crates/loopd/src/http.rs (423 lines): Request/Head/HttpError, send (exact header order, no `Content-Length` for GET), read_head (buffers across timeouts; `Timeout`/`Closed`/`TooLarge`/`Malformed`), parse_status+parse_head (`HTTP/1.1`/`HTTP/1.0`, status 100-599, lowercased names, duplicates kept, trimmed values), body (chunked/length/close; chunk extensions + trailers skipped), and read_capped. Two fixes: the chunk `Data` phase jumped to `Crlf` on `take==want`, but `want` was capped by the caller's buffer so it switched mid-chunk and returned `malformed chunk` on the recorded fixture — changed to switch on `chunk_remaining==0`; `read_length` reads straight into the caller buffer instead of an 8192 temp slice that would panic for readers larger than 8192. First gate failed on three clippy lints (needless borrows of `format!` results and `map_or` -> `is_some_and`), fixed on the second run. All 15 tests pass and `make gate` prints `gate: ok`. |
 | M2a/05-loopd-sse | 2026-09-18 | done | 2 | fail | none | Added `pub mod sse;` to crates/loopd/src/lib.rs and wrote crates/loopd/src/sse.rs: SseItem (Data, Done), SseError (Io, Timeout, Truncated, LineTooLong, NotUtf8) with Display/std::error::Error, and Events<R> which reads a line in bounded 4096-byte chunks, skipping blank/comment/other-field lines and stripping `data:` plus one leading space, decoding UTF-8 only once a whole line has arrived. Two fixes: `drain(..pos)` left the newline in the buffer so blank lines never advanced — changed to `drain(..=pos)` and pop the endings; `process_line` returns `Ok(None)` for a skipped line, which collided with `next_item`'s "stream ended" `Ok(None)` — restructured so a skip continues the loop and only a clean EOF sets `ended`. Both LineTooLong checks (mid-arrival and whole-read) verified by checking the accumulated length before reading and the finished line length. All 7 tests pass; first gate run failed on an unused import, fixed. |
 | M2a/06-llama-request | 2026-09-18 | done | 1 | pass | none | Added `pub mod llama;` to crates/loopd/src/lib.rs and wrote crates/loopd/src/llama/mod.rs (ChatMessage, ToolSchema, ChatRequest, ChatEvent, FinishReason, Timings with the server's deserialize shape, Completion, InferError with Display/std::error::Error, and a Client holding the config) and crates/loopd/src/llama/request.rs. build_body serializes the body from `#[derive(Serialize)]` structs so key order is fixed; each message kind is serialized with its own struct (the assistant renders `content` as `""` when `None`, and leaves `reasoning_content`/`tool_calls` out when absent; the top-level `tools` array is omitted when empty; `type` comes from `#[serde(rename = "type")]`); the first `cargo build` after writing the structs missed the `role` field on every message struct, caught by the failing test compile, added. 5 request tests pass; `make gate` prints `gate: ok`. |
+| M2a/07-llama-assemble | 2026-09-18 | done | 3 | fail | none | Wrote crates/loopd/src/llama/assemble.rs (Assembler plus server-format Chunk/Choice/Delta/ToolCallPiece/FunctionPiece/PromptProgress structs with no deny_unknown_fields) and registered `pub mod assemble;`. Accumulation: text goes through get_or_insert_with so content/reasoning stay None until a non-empty piece arrives; tool-call pieces land by index via u32::try_from then usize::try_from and get_mut, a new call only at exactly the end, a skip-ahead or an out-of-range index is Protocol; timings update before the reasoning-token count reads predicted_n; finish checks finish_reason (StreamClosedEarly), then id, then every tool call has id and name. First gate failed on two clippy collapsible_if lints; rewrote the two nested ifs as edition-2024 let-chains and re-ran. All 7 assemble tests pass; `make gate` prints `gate: ok`. |
 
 ## Reviews