v0.4.0

What's Changed

• feat(networks): scaffold core package (data model + solver seam) by @rpintassilgo in #63
• feat(networks): star routing (r.cost/r.drain per source→sink) by @rpintassilgo in #64
• feat(settings): add experimental Network-mode toggle by @rpintassilgo in #65
• feat(networks): Single/Network mode on the LCP tab (experimental) by @rpintassilgo in #66
• refactor(core+ui): group cost-factor modules and tabs into subpackages by @rpintassilgo in #68
• feat(networks): Level 2a — shared trunks as a graph (per-segment flow) by @rpintassilgo in #70
• feat(networks): Level 2b — network Price Estimation (per-segment diameter + junction boosters) by @rpintassilgo in #72
• fix(ui): light-mode legibility + tab layout polish by @rpintassilgo in #77
• chore(release): 0.4.0 by @rpintassilgo in #78

Full Changelog: v0.3.0...v0.4.0