docs(code): drop the references to a plan file that no longer exists

Seven comments pointed at sections of `~/next/improve-downloads.md`, which is
not in the tree and not anywhere a reader of this repository can follow. Each
now states the thing it was citing: why a paused transfer holds nothing, why the
lease is taken after the save target and not before, why a chunk request marks
a lease alive, where the leaseless bound's number comes from.

The leaseless comment also said "two files at a time" three paragraphs under
`MAX_LEASELESS_IN_FLIGHT = 12`, left behind when the bound was raised. A comment
that contradicts the constant beside it is worse than no comment: one of them is
wrong and the reader cannot tell which.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AsoWC3GmhNdwVFomW3QjH3

4 files changed, 10 insertions, 9 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/static/downloads.js b/packages/meshbay-hub/src/meshbay_hub/static/downloads.js
index c790394..9c23d3c 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/downloads.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/downloads.js
@@ -649,8 +649,9 @@ async function _attemptStreamedDownload(filename, size, attempt,
     // writing to the stream stalls that download where we cannot see it or
     // resume it, and an idle worker is terminated within seconds, taking the
     // stream with it. A pause button here would restart from zero, which is
-    // worse than not offering one. §6.5 of ~/next/improve-downloads.md records
-    // what giving Firefox and Safari a resumable target would cost.
+    // worse than not offering one. Offering Firefox and Safari a resumable
+    // target means a resumable sink of our own, which is a larger piece of work
+    // than the button it would enable.
     pausable: false,
     writable: {
       write: (bytes) => { lastWrite = Date.now(); return writer.write(bytes); },
diff --git a/packages/meshbay-hub/src/meshbay_hub/static/file-utils.js b/packages/meshbay-hub/src/meshbay_hub/static/file-utils.js
index 99d9f9a..b732734 100644
--- a/packages/meshbay-hub/src/meshbay_hub/static/file-utils.js
+++ b/packages/meshbay-hub/src/meshbay_hub/static/file-utils.js
@@ -451,9 +451,9 @@ async function downloadEntry(transfers, transport, gek, entry) {
     },
 
     // After the target, never before: a granted slot has to be taken up within
-    // the node's deadline, and opening a target can outlast it. See §8.1 of
-    // ~/next/improve-downloads.md — the other order was tried and cost two of
-    // three downloads.
+    // the node's deadline, and opening a target can outlast it — a Save As
+    // dialog waits for a person. Asking for the slot first loses it to the
+    // grant deadline while the dialog is open.
     makeLease: () => transport.openTransfer({
       kind: 'download', bytes: entry.size, chunks: totalChunks }),
 
diff --git a/packages/meshbay-hub/tests/test_client_version_gate.py b/packages/meshbay-hub/tests/test_client_version_gate.py
index 69ca062..4dc9b98 100644
--- a/packages/meshbay-hub/tests/test_client_version_gate.py
+++ b/packages/meshbay-hub/tests/test_client_version_gate.py
@@ -5,9 +5,9 @@ The SPA is served by the hub, so a browser picks up a new client on reload. The
 desktop application **ships its own interface**, so on a flag day an un-updated
 one can still sign in, still list groups, and then fail every connection with
 `version_too_old` — a refusal in a protocol vocabulary, surfacing as a node that
-will not talk, with nothing anyone can act on. §12.3 of
-~/next/improve-downloads.md named this as the thing that had to exist before
-MNP 3.0 could ship.
+will not talk, with nothing anyone can act on. Refusing at the handshake is only
+honest if something tells the person *before* they get there, and this is that
+something.
 
 `compareVersions` and `refuseIfTooOld` are lifted out of `main.js` **as text**
 and executed against a modelled environment, on the rule this repo follows
diff --git a/packages/meshbay-hub/tests/test_transfers.py b/packages/meshbay-hub/tests/test_transfers.py
index d93cf80..a776b50 100644
--- a/packages/meshbay-hub/tests/test_transfers.py
+++ b/packages/meshbay-hub/tests/test_transfers.py
@@ -560,7 +560,7 @@ def test_a_transport_is_not_closed_under_a_preparing_transfer(tmp_path):
 # The rule the whole design turns on: **a paused transfer holds nothing.** Its
 # slot goes back to the node the moment it stops, and resuming rejoins the queue
 # at the tail. Anything else lets one member close a node by pausing four
-# downloads and going to lunch (§6.2 of ~/next/improve-downloads.md).
+# downloads and going to lunch.
 
 
 def _pausable_run():