rebrand to notevi: one CLI over the jj sidecar

vr and vrsite become a single binary. vrsite/ folds into a web package in
one module (0x4200.cafe/notevi); "notevi web" serves and exports exactly
what vrsite did, and "notevi read/grep/note/query" is unchanged.

The sidecar is renamed with it: notevi_log, notevi-log.jsonl, and the
description "private: notevi log". The pre-rebrand names are still
recognized, so an old repository opens and reads; it is renamed in place
on the first write, or up front with "notevi migrate DIR...".

That rename cannot be a single mv inside jj run. jj only auto-tracks a
*new* file in the run working copy below a size limit it does not take
from the command line, so writing a whole log under a name the change has
never held is silently dropped while jj reports success. ensureLogFile
creates the file empty first and lets every later byte be a modification
of a tracked file, which snapshots at any size; that also fixes the same
latent bug when importing a large legacy vr-log.jsonl.

Adds a bem-te-vi mark (favicon and nav brand) and a README.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

1 files changed, 56 insertions, 0 deletions

diff --git a/web/log.go b/web/log.go
new file mode 100644
index 0000000..b45eec5
--- /dev/null
+++ b/web/log.go
@@ -0,0 +1,56 @@
+package web
+
+import (
+	"fmt"
+	"os"
+	"sync"
+)
+
+// logStore is implemented by the production jj sidecar and by the file-backed
+// adapter used in tests. Append's callback makes session note numbering atomic
+// with the content update.
+type logStore interface {
+	Read() ([]byte, error)
+	Generation() (string, error)
+	Append(func(current []byte) ([]byte, error)) error
+	String() string
+}
+
+type fileLog struct {
+	path string
+	mu   sync.Mutex
+}
+
+func newFileLog(path string) *fileLog { return &fileLog{path: path} }
+
+func (l *fileLog) String() string { return l.path }
+
+func (l *fileLog) Read() ([]byte, error) { return os.ReadFile(l.path) }
+
+func (l *fileLog) Generation() (string, error) {
+	info, err := os.Stat(l.path)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%d:%d", info.Size(), info.ModTime().UnixNano()), nil
+}
+
+func (l *fileLog) Append(makePayload func(current []byte) ([]byte, error)) error {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	current, err := os.ReadFile(l.path)
+	if err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	payload, err := makePayload(current)
+	if err != nil {
+		return err
+	}
+	f, err := os.OpenFile(l.path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	_, err = f.Write(payload)
+	return err
+}