fix: remove Python CLI entry point — Rust binary is the only CLI

Root cause of issue #8: pip install created a Python 'prism' script
that shadowed the Rust binary. The Python CLI only has old commands
(setup, configure, run) — not login, node, query, ingest, mesh.

Fix:
- Removed [project.scripts] prism entry point from pyproject.toml
- The Rust binary is the ONLY way to run prism
- Python layer is invoked BY the Rust binary via prism-python-bridge
- install.sh downloads Rust binary to ~/.local/bin/prism (after pip)
- native-release.yml fixed (libcurl + dashboard placeholder + permissions)
- Binaries now on release: prism-linux-x86_64.tar.gz (55MB),
  prism-macos-aarch64.tar.gz (38MB)

Also included:
- Streaming markdown buffer (Tier 2.1)
- Python fallback commands give clear 'install Rust binary' message

Closes #8

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: Darth-Hidious

app/backend/ui_emitter.py

@@ -13,6 +13,7 @@
     ToolApprovalRequest,
 )
 from app.backend.protocol import make_event
+from app.backend.stream_buffer import MarkdownStreamBuffer
 from app.backend.tool_meta import detect_result_type, TOOL_VERBS
 from app.backend.status import build_status
 
@@ -55,6 +56,7 @@ def process(self, user_input: str) -> Generator[dict, None, None]:
         plan_buffer = ""
         in_plan = False
         tool_start_time = None
+        stream_buf = MarkdownStreamBuffer()
 
         for event in self.agent.process_stream(user_input):
             if isinstance(event, TextDelta):
@@ -97,11 +99,14 @@ def process(self, user_input: str) -> Generator[dict, None, None]:
                         plan_buffer += event.text
                     continue
 
-                # Normal text streaming
-                yield make_event("ui.text.delta", {"text": event.text})
+                # Normal text streaming — buffered at safe markdown boundaries
+                for chunk in stream_buf.push(event.text):
+                    yield make_event("ui.text.delta", {"text": chunk})
 
             elif isinstance(event, ToolCallStart):
-                # Flush any accumulated text before the tool starts
+                # Flush buffer + accumulated text before the tool starts
+                for chunk in stream_buf.flush():
+                    yield make_event("ui.text.delta", {"text": chunk})
                 if accumulated_text.strip():
                     yield make_event("ui.text.flush", {"text": accumulated_text})
                     accumulated_text = ""

pyproject.toml

@@ -94,8 +94,10 @@ dev = [
     "flake8>=6.1.0",
 ]
 
-[project.scripts]
-prism = "app.cli.bootstrap:main"
+# No Python entry point — the Rust binary IS the CLI.
+# Python is invoked by the Rust binary via prism-python-bridge.
+# [project.scripts]
+# prism = "app.cli.bootstrap:main"  # REMOVED — conflicts with Rust binary
 
 [project.urls]
 Homepage = "https://github.com/Darth-Hidious/PRISM"