fix: backport stages.py \b-parser fix + drawer-finish inline (uncommitted from 1.0.0-55)

The chunk-read parser fix that ships as part of 1.0.0-55 in the
running container was scp'd to maple but never reached git. Same
for the drawer-job-finish margin-left removal (request: pill
sits inline next to operator/date, not flush right).

Reconciling source with deployed state. No new behaviour — git
now matches what's been live on maple since 1.0.0-55.

app/burnin/stages.py

@@ -543,11 +543,37 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
 
                 async def _drain(stream, is_stderr: bool):
                     nonlocal bad_blocks_total, pid_seen
-                    async for raw in stream:
-                        line = raw if isinstance(raw, str) else raw.decode("utf-8", errors="replace")
+                    # Chunk-read instead of line-iterate. badblocks emits
+                    # progress with '\b' backspaces (and sometimes '\r')
+                    # to overwrite the previous progress line in-place —
+                    # there's no '\n' between updates until a phase
+                    # transition. async-for-line would buffer the entire
+                    # phase's output as ONE line, so the parser never
+                    # sees mid-phase percent updates. We read raw chunks,
+                    # normalize \b runs + \r to \n, then process each
+                    # resulting fragment as a line. Keep the partial
+                    # trailing fragment in buf for the next chunk.
+                    buf = ""
+                    while True:
+                        chunk = await stream.read(4096)
+                        if not chunk:
+                            break
+                        if isinstance(chunk, bytes):
+                            chunk = chunk.decode("utf-8", errors="replace")
+                        buf += chunk
+                        # Normalize \b runs + lone \r to \n so split() works.
+                        normalized = _re_pre.sub(r"[\b]+", "\n", buf)
+                        normalized = normalized.replace("\r", "\n")
+                        fragments = normalized.split("\n")
+                        # The tail is incomplete — keep it for the next chunk.
+                        buf = fragments[-1]
+                        for fragment in fragments[:-1]:
+                            line = fragment + "\n"
+                            if not line.strip():
+                                continue
 
-                        # First stdout line is "PID:<n>" from the wrapping shell.
-                        # Capture it and don't append it to the user-visible log.
+                            # First stdout line is "PID:<n>" from the
+                            # wrapping shell. Capture and skip.
                             if not is_stderr and not pid_seen and line.startswith("PID:"):
                                 pid_seen = True
                                 try:
@@ -560,11 +586,10 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
                                     pass
                                 continue
 
-                        # Drive progress.update from EVERY stderr line so it
-                        # picks up the "Testing with pattern 0xXX" + "Reading
-                        # and comparing" headers (which advance the phase
-                        # counter), not just the percent-done lines. CPU-
-                        # bound regex work, no I/O, safe to do unconditionally.
+                            # Drive progress.update from EVERY stderr line
+                            # so it picks up "Testing with pattern 0xXX" +
+                            # "Reading and comparing" headers, not just
+                            # the percent-done lines. CPU-bound regex.
                             prev_phase = progress.phase
                             phase_changed = False
                             is_progress_line = False
@@ -578,22 +603,18 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
                                     bad_blocks_total += 1
 
                             # Keep the "XX% done" lines OUT of output_lines.
-                        # They're the dominant volume (sub-second cadence
-                        # for hours) and the log_text concat is quadratic
-                        # in length. Headers, errors, bad-block numbers,
-                        # and other diagnostic output still get logged.
+                            # They're the dominant volume; log_text concat
+                            # is quadratic.
                             if not is_progress_line:
                                 output_lines.append(line)
 
-                        # Single throttle gate covering EVERY DB touch in
-                        # this loop. Without this, _is_cancelled + percent
-                        # writes + chunk-log appends collectively overwhelm
-                        # the asyncio loop, the asyncssh drain falls behind,
-                        # the SSH window stops advancing, sshd stops reading
-                        # the pipe, badblocks blocks on pipe_write and no
-                        # disk I/O happens. Symptom: badblocks pid in
-                        # wchan=pipe_write with /sys/block sectors_written
-                        # delta of 0.
+                            # Single throttle gate covering EVERY DB touch.
+                            # Without this, the cumulative DB load makes
+                            # the asyncssh drain fall behind, the SSH
+                            # window stops advancing, sshd stops reading
+                            # the pipe, badblocks blocks on pipe_write
+                            # and no disk I/O happens (sectors_written
+                            # delta of 0 confirmed the symptom).
                             now_ts = time.monotonic()
                             time_since_last_db = now_ts - last_db_write_ts
                             should_write = phase_changed or time_since_last_db >= BB_DB_MIN_SECONDS
@@ -621,8 +642,8 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
                                     job_id, "surface_validate", bad_blocks_total,
                                 )
 
-                            # 3) Throughput. Skip phase transitions (per-
-                            # phase pct resets would yield a negative delta).
+                                # 3) Throughput. Skip phase transitions
+                                # (per-phase pct resets → negative delta).
                                 if (
                                     drive_size_bytes
                                     and not phase_changed
@@ -636,10 +657,7 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
                                         job_id, "surface_validate", mbps,
                                     )
 
-                            # 4) Log flush. Chunk what's accumulated since
-                            # the last write. log_text concat is quadratic
-                            # so the volume reduction from skipping "% done"
-                            # lines above matters MORE than the throttle.
+                                # 4) Log flush.
                                 if pending_log_chunks:
                                     chunk = "".join(pending_log_chunks)
                                     pending_log_chunks.clear()

app/static/app.css

@@ -2951,7 +2951,6 @@ th.sort-desc::after {
   flex-wrap: wrap;
 }
 .drawer-job-finish {
-  margin-left: auto;
   display: inline-flex;
   align-items: baseline;
   gap: 8px;