report: add BuildView/Prompter ports and drive pkh build through them

Core flows no longer reach into the terminal UI: build_source_package
takes a BuildSourceOptions struct (source tree, domain options, view,
prompter) and reports phases, messages and outcomes through the
environment-agnostic ports in the new report module. The classifiers
move from ui/logfmt to the core logfmt module, DebUi becomes a
BuildView adapter, the re-vendor retry asks the prompter instead of
checking for a TTY, and artifact/success printing moves to the CLI.

Headless consumers pass report::Quiet; an embedding (e.g. a builder
server forwarding events to a web frontend) implements BuildView and
maps the plain-data events onto its own wire format.

src/deb/local.rs

@@ -2,8 +2,8 @@
 /// Directly calling 'debian/rules' in current context
 use crate::context::{Context, ContextCommand, LineSink};
 use crate::deb::find_dsc_file;
+use crate::logfmt::QuiltClassifier;
 use crate::ui::deb::{DebUi, Phase};
-use crate::ui::logfmt::QuiltClassifier;
 use log::warn;
 use std::collections::{BTreeMap, HashMap};
 use std::error::Error;