feat(diagnostics): the issue composer — draft, review, screenshots, zip export (E16 S3)

After Stop (or at the cap, or from Settings → Diagnosztika's past sessions)
one dialog drafts the issue: title, description, the steps drafted from the
session's markers and page changes (a marker without a label is named by its
time), the environment (version, browser, system, window, language). Beside
it, what goes with it: the browser and server logs — each reviewable line by
line, an unticked line is not sent — and the screenshots, removable, with
paste / drop / pick to add more.

- it saves as it goes (debug_sessions.draft, migration 0090): the rendered
  markdown in the user's language, the excluded rows, and its own fields to
  reopen as it was; a sent session is read-only
- the zip export (issue.md, client.log, server.log, screenshots) is built
  from the saved draft by app/issues/bundle.py — the one definition the Gitea
  delivery (S4) will share; .log, not .jsonl, which Gitea refuses
- the log line's level tags and clock move to components/logLineParts so the
  review list draws a level the way both log viewers do

backend/app/debugsession.py

@@ -127,6 +127,13 @@ def level_for(user: User, session: DebugSession | None) -> tuple[str, datetime |
     return session.level, session.until
 
 
+def save_draft(session: DebugSession, draft: dict) -> None:
+    """Keep the composer's draft (the caller validated and commits). Shape: `title`, `body` (the
+    rendered markdown an export or an issue carries), `excluded` (log row ids taken out of the
+    evidence) and `form` (the composer's own fields, to reopen it as it was)."""
+    session.draft = draft
+
+
 def serialize(session: DebugSession | None, screenshots: int = 0) -> dict | None:
     if session is None:
         return None
@@ -139,6 +146,7 @@ def serialize(session: DebugSession | None, screenshots: int = 0) -> dict | None
         "ended_reason": session.ended_reason,
         "issue_url": session.issue_url,
         "screenshots": screenshots,
+        "draft": session.draft,
     }
 
 
@@ -231,23 +239,24 @@ def _evidence(session: DebugSession):
     return (LogEvent.debug_session_id == session.id, not_(upload_line.is_(True)))
 
 
-def bundle(db: Session, session: DebugSession) -> tuple[list[LogEvent], int]:
+def bundle(
+    db: Session, session: DebugSession, *, drop_excluded: bool = False
+) -> tuple[list[LogEvent], int]:
     """The session's log rows, browser and server interleaved in time, capped at BUNDLE_MAX — and
-    how many rows it has in all, so a cut bundle can say so."""
+    how many rows it has in all, so a cut bundle can say so. `drop_excluded` leaves out the rows
+    the user took out in the composer: what an export or an issue carries."""
+    where = list(_evidence(session))
+    excluded = (session.draft or {}).get("excluded") or [] if drop_excluded else []
+    if excluded:
+        where.append(LogEvent.id.not_in(excluded))
     rows = list(
         db.scalars(
-            select(LogEvent)
-            .where(*_evidence(session))
-            .order_by(LogEvent.ts, LogEvent.id)
-            .limit(BUNDLE_MAX)
+            select(LogEvent).where(*where).order_by(LogEvent.ts, LogEvent.id).limit(BUNDLE_MAX)
         )
     )
     total = len(rows)
     if total == BUNDLE_MAX:
-        total = (
-            db.scalar(select(func.count()).select_from(LogEvent).where(*_evidence(session)))
-            or total
-        )
+        total = db.scalar(select(func.count()).select_from(LogEvent).where(*where)) or total
     return rows, total