feat(psychometric): recover ESEM loadings and refuse reverse DSEM lags

.codegraph/.gitignore

@@ -0,0 +1,5 @@
+# CodeGraph data files — local to each machine, not for committing.
+# Ignore everything in .codegraph/ except this file itself, so transient
+# files (the database, daemon.pid, sockets, logs) never show up in git.
+*
+!.gitignore

ARCHITECTURE.md

@@ -61,6 +61,7 @@ boundaries above remain the target modular MSA architecture.
 | `tepp_simulation` | known-truth temporal/event data generation |
 | `validation_core` | RMSE, bias, coverage, graph, and Monte Carlo metrics |
 | `tepp_api` | versioned DTO, schema, and export contracts |
+| `psychometric_fit` | CPU `f64` ESEM loading recovery and event-time DSEM lag gates |
 
 No crate exposes placeholder production behavior in Task 1. This prevents an
 empty façade from becoming a de facto public API before its invariants and tests

CHANGELOG.md

@@ -6,6 +6,7 @@ All notable changes to TEPP are documented here. The format follows Keep a Chang
 
 ### Added
 
+- `psychometric_fit` CPU `f64` ESEM/DSEM fit: exploratory OLS recovers known cross-loadings from admitted log-ratio or logistic-normal coordinates with computed RMSE below a zero-loading collapse; reverse or zero event-time lagged paths fail closed; a good global fit cannot reclassify formative or network constructs as reflective (ADR 0005). No new migration number (`#45` still owns `0007`).
 - `tepp_api` naruon live loopback HTTP/1.1 listener: `serve_one` installs a read/write deadline, requires a loopback `Host`, refuses `Transfer-Encoding` and NIM/proxy credential headers, parses `knowledge_cutoff` as RFC 3339 and refuses a future cutoff, keys analysis-run idempotency by tenant plus key, and proves both analysis-run and export POSTs over a real `TcpStream`. Not a production TLS/`$PORT` service (ADR 0011).
 - `tepp_api` adaptive orchestration router (ADR 0010): versioned `direct`/`verify`/`committee`/`conductor`/`abstain` selection from CPU `f64` risk, ambiguity, evidence, and token-budget inputs; recorded stages, recursion, decomposition, access lists, and role-specific reasoning effort; fail-closed document-controlled policy/access/credentials; LLM plans remain proposals under deterministic statistical authority; comparable-budget ablation requires a direct baseline; credential-free contextual-orchestrator binding. Live NIM HTTP remains accepted-target.
 - `tepp_api` purpose-bound provider-payload minimization: time-bounded `PurposeGrant` evaluation, fail-closed expired/not-yet-valid/inverted/cross-tenant/impossible-calendar denial, semantic UTC calendar validation, refusal to copy identity mappings into model-provider payloads or ordinary logs, preservation of opaque analytical identifiers and membership roles (no blanket PII mask), a separately authorized scientific re-identification path, and an internally bound FIPS 180-4 SHA-256 audit digest appended through `ReidentificationAuditSink` before disclosure.

Cargo.toml

@@ -11,6 +11,7 @@ members = [
     "crates/tepp_simulation",
     "crates/validation_core",
     "crates/tepp_api",
+    "crates/psychometric_fit",
 ]
 default-members = [
     "crates/evidence_core",
@@ -23,6 +24,7 @@ default-members = [
     "crates/tepp_simulation",
     "crates/validation_core",
     "crates/tepp_api",
+    "crates/psychometric_fit",
 ]
 
 [workspace.package]

README.md

@@ -7,7 +7,7 @@ implemented in Rust.
 ## Current implementation state
 
 This branch establishes the Task 1 Rust workspace and quality-gate foundation.
-The ten bounded crates compile independently but intentionally expose no
+The eleven bounded crates compile independently but intentionally expose no
 placeholder production APIs. Domain behavior begins in Task 2 with immutable
 evidence identifiers and source records.
 
@@ -22,6 +22,7 @@ crates/corpus_split
 crates/tepp_simulation
 crates/validation_core
 crates/tepp_api
+crates/psychometric_fit
 ```
 
 ## Local verification

crates/psychometric_fit/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "psychometric_fit"
+description = "CPU f64 ESEM loading recovery and event-time DSEM lag gates."
+version.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+authors.workspace = true
+repository.workspace = true
+homepage.workspace = true
+readme.workspace = true
+keywords.workspace = true
+categories.workspace = true
+publish = false
+
+[lints]
+workspace = true

crates/psychometric_fit/src/error.rs

@@ -0,0 +1,80 @@
+//! Fail-closed ESEM/DSEM fit errors.
+
+use std::fmt;
+
+/// A fail-closed psychometric-fit error.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+#[non_exhaustive]
+pub enum PsychometricFitError {
+    /// Raw simplex proportions were offered as Euclidean fit inputs.
+    RawProportionForbidden,
+    /// Empty, rank-unsupported, unequal-length, or non-finite numeric input.
+    InvalidNumericInput,
+    /// A predictor matrix has a singular Gram matrix.
+    SingularDesign,
+    /// A lagged path would move backward or stay put in event time.
+    ReverseEventTimePath,
+    /// A good global fit was used to reinterpret a formative or network
+    /// construct as reflective.
+    FormativeReinterpretationForbidden,
+    /// The construct class is unresolved, so reflective interpretation is
+    /// unavailable.
+    UnresolvedConstruct,
+}
+
+impl fmt::Display for PsychometricFitError {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let message = match self {
+            Self::RawProportionForbidden => {
+                "raw topic proportions are forbidden psychometric fit inputs"
+            }
+            Self::InvalidNumericInput => "invalid psychometric fit numeric input",
+            Self::SingularDesign => "singular psychometric fit design matrix",
+            Self::ReverseEventTimePath => "DSEM lagged paths cannot move backward in event time",
+            Self::FormativeReinterpretationForbidden => {
+                "formative or network constructs cannot be reinterpreted as reflective"
+            }
+            Self::UnresolvedConstruct => "construct class is unresolved",
+        };
+        formatter.write_str(message)
+    }
+}
+
+impl std::error::Error for PsychometricFitError {}
+
+#[cfg(test)]
+mod tests {
+    use super::PsychometricFitError;
+
+    #[test]
+    fn error_messages_are_stable() {
+        for (error, message) in [
+            (
+                PsychometricFitError::RawProportionForbidden,
+                "raw topic proportions are forbidden psychometric fit inputs",
+            ),
+            (
+                PsychometricFitError::InvalidNumericInput,
+                "invalid psychometric fit numeric input",
+            ),
+            (
+                PsychometricFitError::SingularDesign,
+                "singular psychometric fit design matrix",
+            ),
+            (
+                PsychometricFitError::ReverseEventTimePath,
+                "DSEM lagged paths cannot move backward in event time",
+            ),
+            (
+                PsychometricFitError::FormativeReinterpretationForbidden,
+                "formative or network constructs cannot be reinterpreted as reflective",
+            ),
+            (
+                PsychometricFitError::UnresolvedConstruct,
+                "construct class is unresolved",
+            ),
+        ] {
+            assert_eq!(error.to_string(), message);
+        }
+    }
+}