PowerTree v0.9.0

The "most useful and user-friendly" release — implements the competitive
audit vs. LTpowerPlanner (docs/AUDIT-2026-08-08-competitive.md), keeping
everything deliberately small.

• SI-suffix value entry everywhere: type 100m, 4.7u, 2.2k,
  50 mΩ in any electrical field; engineering-notation display; invalid
  input flags red instead of silently mangling.
• Cost + board-area fields (optional, per element) with per-tree
  rollups in the executive summary, HTML report, Excel, CLI and library
  parts — the LTpowerPlanner comparison axes, vendor-neutral.
• Compare architectures (Project menu, Ctrl+Shift+A; CLI compare;
  MCP tool): every tree side by side on power, efficiency, loss, cost,
  area, growth capacity and findings.
• PMIC modelling pattern: Quad-output PMIC template + user-guide
  section — one block, one converter per rail, shared refdes and Iq;
  electrically exact for DC budgeting without a DAG rewrite.
• Gesture polish: clickable datasheet links (↗), F2 / double-click
  rename, double-click a block outline to collapse (and a summary node to
  expand), first-run empty-canvas hint.

Explicit non-changes (per the audit's no-over-engineering rule): no SPICE,
no vendor part database, no cloud, no DAG, no UI modes.

PowerTree v0.8.0

Implements every actionable finding of the v0.7.0 audit
(docs/AUDIT-2026-08-07.md); deferred architecture items are designed in
docs/ROADMAP.md.

Scale & responsiveness (P0)

• Rail-grid wrapping: many leaf loads on one rail lay out as a compact grid
  with a single bus edge — a 501-element board is 7.4× narrower (135k px →
  18k px). Threshold configurable (Settings / per view), off in custom mode.
• Click-to-navigate minimap overlay (toggleable).
• Exports run in worker threads with a busy dialog — no more 8-second GUI
  freezes; renders cap their longest side (16k px) by auto-reducing scale.
• Jump-to-finding / search-Enter now auto-expands collapsed branches and
  blocks hiding the target.
• Editing: drag-drop re-parenting in the list view (model-validated),
  multi-select delete, and subtree copy/paste (Ctrl+Alt+C/V) via the OS
  clipboard — works across trees, projects and app instances.

Model depth (P1)

• Resistive loads (I = V/R, solved in the corner fixed-point).
• Load duty cycle: min/typ corners budget the duty-weighted average draw;
  the max corner keeps the full peak.
• Unregulated converter topology: Vout = ratio × Vin, tracking per corner.
• Power-up sequencing: converters carry a sequence step; a rail enabling
  before its input rail is flagged.
• Library maturity: parts stamped with version/author/date (version bumps
  on overwrite), import-conflict handling (overwrite/rename/skip), export
  the whole library, and a project-local library (powertree_library.json
  next to the .ptproj — commit it with the design).
• Reports: embedded project logo on PDF/HTML titles, pre-export tree
  selection, include/exclude waived findings.
• Nets view/report now state their scope explicitly (name registry;
  cross-tree merged solving is a roadmap item).

Usability (P2)

• Command palette (Ctrl+K) searching every menu action.
• Message log dock — status messages persist with timestamps.
• Arrow-key navigation on the canvas (parent/child/siblings).
• Print style now applies a light theme to the whole app window.

Process (P3)

• CI: ruff lint gate, coverage floor, and a Linux test leg.
• Version single-sourced from powertree.version.
• Releases: the publish workflow now creates the GitHub Release with the
  Windows installer zip and wheels attached, notes taken from this file.
• CONTRIBUTING.md + issue templates.
• Rotating file log (%APPDATA%/PowerTree/powertree.log) + GUI crash dialog.
• .ptproj migration framework (versioned upgrade registry).
• Autosave now also protects never-saved projects (startup recovery).
• README gained screenshots.