…s stream (Phase 2)

- Filter DSL via --where: =, !=, >, >=, <, <=, ~regex, !~regex, ?, !?
  with dot-path support for nested fields (e.g. --where "user.age>18")
- --first exits after first entity matches filter criteria
- --select projects specific fields (comma-separated dot paths)
- --ops filters by operation type (upsert, patch, delete)
- --no-dna outputs NO_DNA v1 agent-friendly envelope format with
  lifecycle events (connected, snapshot_complete, entity_update, disconnected)
- --count shows running update count on stderr
- 9 unit tests for filter parsing and evaluation

…hase 3)

- --save <file> records all raw frames with timestamps to a JSON file
- --duration <secs> auto-stops recording after N seconds
- --load <file> replays a saved snapshot through the same merge/filter
  pipeline (no WebSocket connection needed)
- Snapshot format includes metadata (view, url, captured_at, duration)

…ase 4)

EntityStore tracks full entity state + per-entity history ring buffer
(default 1000 entries). Supports:
- --history: outputs full update history for --key entity as JSON array
- --at N: shows entity state at specific history index (0 = latest)
- --diff: shows field-level diff (added/changed/removed) between updates
  with raw patch data when available

These flags provide non-interactive agent equivalents of the TUI time
travel feature. 5 unit tests for store operations and diffing.

Behind --features tui flag, `hs stream --tui` launches a ratatui-based
terminal UI with:
- Split-pane layout: entity list (30%) + detail view (70%)
- Entity navigation (j/k, arrows), detail focus (Enter/Esc)
- Time travel through entity history (h/l, Home/End)
- Diff view toggle (d) showing field-level changes
- JSON syntax coloring in detail panel
- Pause/resume live updates (p)
- Save snapshot to file (s)
- Entity key filtering (/)
- Raw frame toggle (r)
- Status bar with keybinding hints
- Timeline bar showing history position

Dependencies: ratatui 0.29, crossterm 0.28 (optional)
Without the tui feature, --tui prints an error with install instructions.

The server sends subscribed acknowledgments as binary frames with a
different shape (no `entity` field), causing parse_frame to fail.
Now falls back to try_parse_subscribed_frame before warning, so real
parse errors are still surfaced while subscribed frames are handled
cleanly. Re-exports try_parse_subscribed_frame from hyperstack-sdk.

Previously, keys like r, d, s, h, l etc. were matched as TUI commands
before checking if filter input was active, making it impossible to
type those characters in the filter. Now checks filter_input_active
first and routes all Char keys to the filter text input.

The / filter now recursively searches all string, number, and boolean
values in each entity's JSON data. Typing "test" matches any entity
where any field value contains "test" (case-insensitive), not just
entities whose key contains the search term.

When typing a filter that reduces the entity list, the selection now
clamps to stay within the filtered results. Navigation (j/k) also
bounds against the filtered count instead of the full entity list.

Uses ratatui's ListState with the selected index so the list widget
automatically scrolls to keep the highlighted entity in view when
navigating past the visible area. Also shows filter text and
filtered/total count in the title when a filter is active.

- gg: jump to top of list
- G: jump to bottom of list
- Ctrl+d / Ctrl+u: half-page down/up
- n: jump to next filter match (wraps around)
- Number prefixes: e.g. 10j moves down 10, 5k moves up 5,
  3Ctrl+d moves 3 half-pages down
- Esc clears any pending count/g prefix

ListState was being recreated fresh each frame, losing the scroll
offset. Now stored in App and synced with selected_index on every
action, so ratatui properly auto-scrolls the entity list in both
directions — pressing k after scrolling past the bottom now scrolls
back up as expected.

The timeline bar now shows two distinct pieces of info:
- Row position: "Row 1/513" (your position in the entity list)
- Entity version: "version 1/2" (update history for the selected entity)

Previously only showed "update N/N" which was confusing because it
looked like it referred to list position rather than entity history.

The entity count is already shown in the list panel title, no need
to repeat it in the header bar.

…lisions

Previously --select "a.id,b.id" would output {"id": <b's value>},
silently overwriting a.id. Now uses the full dot-path as the output
key: {"a.id": 1, "b.id": 2}. Single-segment paths are unchanged
(--select "name" still outputs {"name": ...}).

Adds test for the collision case.

raw_frames were only collected when show_raw was active, and were
never read by any rendering code. Now:
- Always collects raw frames (so toggling on shows recent data)
- selected_entity_data() checks show_raw first and returns the most
  recent raw WebSocket frame for the selected entity key

If the TUI panics, disable_raw_mode and LeaveAlternateScreen never
executed, leaving the user's terminal in raw mode (unusable until
running 'reset'). Now installs a panic hook before entering raw mode
that restores the terminal state before re-invoking the original hook.

entity_keys.contains() was O(n) per frame, degrading with thousands
of entities. Now maintains a parallel HashSet<String> for O(1)
membership checks. HashSet::insert returns false if already present,
so it doubles as the contains check. Delete also removes from the set.

- Use strip_suffix instead of manual string slicing for ? and !? suffix
- Use is_some_and/is_none_or instead of map_or for Option comparisons
- Use direct == Some() comparison instead of map_or for equality check

Byte-index slicing panics when the cut point lands in the middle of a
multi-byte codepoint (emoji, CJK characters). Now uses char_indices
to find safe byte boundaries for truncation.

…nfigured

Previously fell through to the first stack with any URL, silently
connecting to an unrelated stack. Now only auto-selects when there is
exactly one stack with a URL (unambiguous), and prints which stack was
chosen. With multiple stacks, requires explicit --url or --stack.

Previously --first only triggered when a --where filter was present,
silently running forever without one. Now --first always exits after
the first output: with --where it exits on first match, without
--where it exits after the first frame (raw) or entity (merged).

Adds comments explaining that two-char operators are checked before
single-char to avoid misparsing, and that the split is on the first
operator occurrence so values may contain operator characters
(e.g. --where "name=a=b" works correctly).

…okups

- Output functions now use a shared BufWriter<Stdout> held in StreamState
  instead of acquiring/releasing stdout lock per call
- Text WebSocket frames parsed once directly to Frame instead of double-
  parsing (Value then Frame)
- diff_at stores entry in local variable instead of 3 redundant gets
- TUI channel buffer increased to 10k for large snapshot batches
- Document that filter cache invalidation is per-tick not per-frame