feat(projection): show staged projection with evidence ladder

Report a projection stage, an evidence ladder and the sustained-regime
write rate from compute_projection, per ADR 0012. A provisional lifespan
appears after 3 observed hours and carries the hours observed and a
short-horizon spread; the complete-local-day condition becomes a fact
instead of a gate, and the write rate replaces the lifespan when no
baseline applies. The TUI and CLI render the stage, ladder count and
full ladder, and drop their own two-sample pre-gates.

src/fenris/tui.py

@@ -18,6 +18,7 @@ from pathlib import Path
 from typing import Any, Callable, Dict, List, Optional
 from zoneinfo import ZoneInfo
 
+from rich.markup import escape
 from rich.text import Text
 from textual.app import App, ComposeResult
 from textual.binding import Binding
@@ -38,8 +39,12 @@ from .activity_plot import VolumePoint, volume_plot
 from .projection import (
     ConfidenceState,
     ProjectionResult,
+    ProjectionStage,
     ScenarioRange,
     compute_projection,
+    ladder_count_text,
+    ladder_lines,
+    write_rate_gb_day,
 )
 from .status import (
     CADENCE_DEFAULT_S,
@@ -2061,12 +2066,6 @@ class FenrisTuiApp(App):
             self._render_headline(
                 "[bold]No observations yet[/bold]\n\n[bold]%s[/bold]" % _RESUME_HINT
             )
-        elif comp.sample_count <= 1 and comp.day_count == 0:
-            # Single sample: awaiting another sample
-            self._render_headline(
-                "[bold]Awaiting another sample[/bold]\n\n"
-                "Collecting usage data — the first projection requires at least two samples."
-            )
         else:
             try:
                 proj = compute_projection(conn, self._clock_now)
@@ -2076,7 +2075,8 @@ class FenrisTuiApp(App):
                 summary, _, context = headline.partition("\n")
                 confidence_title, _, facts = confidence.partition("\n")
                 self._render_headline(summary + "\n" + confidence_title + "\n\n"
-                                      + context + "\n" + facts + "\n" + scenario)
+                                      + context + "\n" + facts + "\n" + scenario
+                                      + "\n\n" + self._format_ladder(proj))
             except Exception:
                 self._render_headline("[bold]No projection available[/bold]")
 
@@ -2267,8 +2267,14 @@ class FenrisTuiApp(App):
     def _format_headline(self, proj: ProjectionResult) -> str:
         """Format the lifespan headline (spec §6.11)."""
         if proj.headline_remaining_seconds is None:
+            if proj.stage == ProjectionStage.NO_OBSERVATIONS:
+                return "[bold]Usage-adjusted theoretical lifespan: [yellow]no projection yet — collecting observations[/yellow][/bold]"
             if proj.zero_rate_fact:
                 return "[bold]Usage-adjusted theoretical lifespan: [red]no finite projection from this history[/red][/bold]"
+            rate = write_rate_gb_day(proj)
+            if rate is not None:
+                return ("[bold]Write rate: %.2f GB/day[/bold]\nNo lifespan without an endurance baseline"
+                        % rate)
             if proj.warming_fact:
                 return "[bold]Usage-adjusted theoretical lifespan: [yellow]%s[/yellow][/bold]" % proj.warming_fact
             return "[bold]Usage-adjusted theoretical lifespan: [red]no projection available[/red][/bold]"
@@ -2295,13 +2301,20 @@ class FenrisTuiApp(App):
         if proj.qualifying_days_progress:
             facts = proj.qualifying_days_progress + " · " + facts
         
-        return "[bold]Projection confidence: [%s]%s[/%s][/bold]\n %s" % (
+        return "[bold]Projection confidence: [%s]%s[/%s] · %s[/bold]\n %s" % (
             color,
-            proj.confidence_state.value,
+            proj.stage_label,
             color,
+            ladder_count_text(proj),
             facts[:1].upper() + facts[1:],
         )
 
+    def _format_ladder(self, proj: ProjectionResult) -> str:
+        """Format the full evidence ladder for the outlook (ADR 0012 §5)."""
+        lines = ["[bold]Evidence ladder[/bold] · %s" % ladder_count_text(proj)]
+        lines.extend(" " + escape(line) for line in ladder_lines(proj))
+        return "\n".join(lines)
+
     def _format_scenario(self, proj: ProjectionResult) -> str:
         """Format scenario range with horizon reasons (spec §6.5)."""
         if not proj.scenario_range: