Resolve the macOS half of the SDD-119 item 3 single-source-of-truth follow-up. The chanora_bridge cdylib macOS deployment-target floor ('10.15') was previously hard-coded at 7 sites across Podfile and chanora_bridge.podspec; this commit collapses them to a single Ruby constant declaration in a new SoT file.
Selected Option B (Ruby constant) over Option A (.xcconfig — rejected because the podspec prepare_command runs before any xcconfig is applied) and Option C (versioned text file — rejected as overkill given both consumers are already Ruby). Realizes SAD-087(a)'s 'single macOS build-configuration location' mandate.
Out of scope: the pbxproj 'MACOSX_DEPLOYMENT_TARGET = 10.15' lines (565/666/717) belong to the PBXProject default config and are independently overridden to '11.0' at the Runner PBXNativeTarget level; they are the Runner app's floor, not the bridge cdylib's floor. The iOS half (IPHONEOS_DEPLOYMENT_TARGET=13.0) remains an open follow-up.
Files: new apps/chanora_flutter/macos/macos_deployment_target.rb (MACOS_BRIDGE_DEPLOYMENT_TARGET = '10.15'.freeze); Podfile + chanora_bridge.podspec require_relative the constant and consume it at 7 sites; docs/architecture/sdd.md SDD-119 item 3 rewritten + Notes bullet updated + v0.9.17 changelog entry.
EdisonJwa
a77a9b2ef2