fix(apply): preserve project name on a name-less re-apply

`upsert_project_tx` defaulted a missing `[project].name` to the slug and then
`ON CONFLICT (slug) DO UPDATE SET name = EXCLUDED.name` wrote that fabricated
value unconditionally — so a re-apply from a clone whose manifest omits `name`
silently clobbered the stored display name back to the slug (visible in
`pic projects ls` / `pic groups ls`).

Bind the raw optional name once and guard both sides on it:
`VALUES ($1, COALESCE($2, $1), $3)` (first apply falls back to the slug for the
NOT NULL column) and `DO UPDATE SET name = COALESCE($2, projects.name)` (a
re-apply updates the name only when the manifest actually declares one). An
omitted optional field now preserves persisted data instead of mutating it.

Pinned by a new `reapply_without_name_preserves_project_name` journey.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/picloud-cli/tests/apply_ownership.rs

@@ -215,6 +215,73 @@ fn claim_conflict_takeover_and_app_inheritance() {
     );
 }
 
+/// The `name` cell (index 1: slug, NAME, owned_groups, created_at) for `project`
+/// in `pic projects ls`.
+fn project_name_cell(env: &common::TestEnv, project: &str) -> String {
+    let ls = common::pic_as(env)
+        .args(["projects", "ls"])
+        .output()
+        .expect("projects ls");
+    let table = String::from_utf8(ls.stdout).unwrap();
+    table
+        .lines()
+        .map(common::cells)
+        .find(|c| c.first() == Some(&project))
+        .and_then(|c| c.get(1).map(|s| (*s).to_string()))
+        .unwrap_or_else(|| panic!("project `{project}` not in projects ls:\n{table}"))
+}
+
+/// A name-less `[project]` re-apply must PRESERVE the display name set on the
+/// first apply — an omitted optional field never clobbers the stored name back
+/// to the slug (regression for the `ON CONFLICT DO UPDATE SET name` path).
+#[ignore = "needs DATABASE_URL pointing at a running Postgres"]
+#[test]
+fn reapply_without_name_preserves_project_name() {
+    let Some(fx) = common::fixture_or_skip() else {
+        return;
+    };
+    let env = common::admin_env(fx);
+    let group = common::unique_slug("name-grp");
+    let proj = common::unique_slug("name-proj");
+    let _g = GroupGuard::new(&env.url, &env.token, &group);
+    common::pic_as(&env)
+        .args(["groups", "create", &group])
+        .assert()
+        .success();
+
+    let dir = manifest_dir();
+    let apply = |m: &str| {
+        fs::write(dir.path().join("picloud.toml"), m).unwrap();
+        common::pic_as(&env)
+            .args(["apply", "--file"])
+            .arg(dir.path().join("picloud.toml"))
+            .assert()
+            .success();
+    };
+
+    // First apply declares a display name.
+    apply(&format!(
+        "[project]\nslug = \"{proj}\"\nname = \"Acme Platform\"\n\n\
+         [group]\nslug = \"{group}\"\nname = \"Grp\"\n"
+    ));
+    assert_eq!(
+        project_name_cell(&env, &proj),
+        "Acme Platform",
+        "the first apply records the declared name"
+    );
+
+    // A re-apply that OMITS `name` must not overwrite it with the slug.
+    apply(&format!(
+        "[project]\nslug = \"{proj}\"\n\n\
+         [group]\nslug = \"{group}\"\nname = \"Grp\"\n"
+    ));
+    assert_eq!(
+        project_name_cell(&env, &proj),
+        "Acme Platform",
+        "a name-less re-apply must preserve the stored name, not clobber it to the slug"
+    );
+}
+
 /// §6/§7 M2 — `[project] parent_group` is the ceiling: applies are refused for
 /// any node not strictly within the attach point's subtree.
 #[ignore = "needs DATABASE_URL pointing at a running Postgres"]