Unflatten dotted paths
Turn flat dotted settings back into an indented outline for a settings editor. Input lines have the exact shape "dotted.path=value" (split at the first "="; a repeated path keeps its final value). Path segments use lowercase letters, digits, and underscores; no path is also a parent of another. Emit the outline as a list of strings: intermediate segments appear as "name:" and each final segment as "name: value", indented 2 spaces per nesting level. Siblings at every level are ordered alphabetically, and a parent line is printed once before its children. Example: ["app.port=8080"] gives ["app:", " port: 8080"].
render_config_tree(lines: list[str]) → list[str][["app.name=api","app.port=8080","debug=false"]]out["app:"," name: api"," port: 8080","debug: false"]State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
[["app.name=api","app.port=8080","debug=false"]]["app:"," name: api"," port: 8080","debug: false"]not run yetsample