* fix(sessions): bound trajectory snapshot and pointer reads
* test(sessions): align oversized snapshot assertion with bounded reader error message
* fix(sessions): cap follow-mode trajectory deltas
ClawSweeper review noted that the trajectory snapshot read was bounded
but the follow-mode delta read (Buffer.alloc(fileState.size - offset))
was not. A runaway trajectory append could still OOM the tail loop.
Reject deltas above TRAJECTORY_RUNTIME_FILE_MAX_BYTES and add regression
coverage for the oversized-delta path.
* test(sessions): exercise trajectory limits through command path
---------
Co-authored-by: Vincent Koc <25068+vincentkoc@users.noreply.github.com>
f92ed16e60