Add graduate student grading policy section

Adds a new section documenting the graduate student grading policy:
- HP (high pass) for major achievements (grant/paper submissions, software releases)
- P (pass) as default for satisfactory progress
- LP/NC for extreme circumstances
- Guidance for internship terms and credit hours
- Margin note directing students to discuss concerns with director

Closes #107

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Co-Authored-By: Claude <[email protected]>

Author: jeremymanning

lab_manual.pdf

@@ -1143,6 +1143,46 @@ \subsection{Authorship guidelines}
   (unless you're presenting or are otherwise playing a key role).
 \end{itemize}
 
+\newthought{Graduate student grading}
+
+\noindent Research terms for graduate students are graded using the following
+scale: HP (high pass), P (pass), LP (low pass), and NC (no credit). The grading
+policy below provides guidance on how these grades are typically assigned.
+
+\marginnote{\texttt{NOTE:} If you have questions or concerns about grading,
+  please talk to \director.}
+
+\textbf{High Pass (HP)} is intended to highlight terms of significant
+achievement or performance substantially above the norm. You will typically
+receive an HP if you accomplish any of the following during the term:
+\begin{itemize}
+\item Submit a new grant or paper
+\item Complete a major revision of a grant or paper
+\item Release a major software package
+\item Complete a major update to an existing software package
+\end{itemize}
+
+\textbf{Pass (P)} is the default grade for graduate students who are making
+satisfactory progress. If you are actively engaged with the lab and making
+reasonable progress on your research, you will receive a P.
+
+\textbf{Low Pass (LP) and No Credit (NC)} are reserved for extreme
+circumstances. For example, if a student is out of touch with the lab for all
+or most of the term without doing any lab-related work or communicating in any
+meaningful way, they may receive an LP or NC. If \director~has concerns about
+your progress during a given term, he will reach out to discuss a plan to
+course correct prior to the end of the term (or the start of the subsequent
+term). Note that receiving multiple LPs can affect your academic standing (e.g.,
+two LPs results in academic probation, and three LPs puts you at risk of losing
+your position in the program).
+
+\textbf{Internship terms} are still graded as research terms even though you
+are not physically present in the lab. If you are on an internship, please
+discuss expectations with \director~at the start of the term.
+
+\textbf{Credit hours:} Research terms may be registered for 1, 2, or 3 credits.
+The grading criteria above apply regardless of the number of credits.
+
 \newthought{Compensation and benefits}
 
 \noindent